problem 1
A train starts at rest, accelerates with constant acceleration a for 5minutes,then travels at constant speed for another 5minutes,and the decelerates with a.suppose it travels a distance of 10km in all find a
problem 2
A ball is dropped from a height of 10m.At the same time, another ball is thrown vertically upwards at an initial speed of 10m/sec.How high above the ground will the two balls collide
problem 3
find the resultant of the two velocity vectors and also, find the angle that the resultant makes with the vector ​

Answers

Answer 1

The constant acceleration of the train is 50/9 m/s².

The two balls will collide at a height of approximately 10.204 meters above the ground.

How to calculate the value

Using the kinematic equations of motion, we have:

distance = initial velocity * time + 1/2 * acceleration * time^2

For the first phase of acceleration, the initial velocity is zero, the time is 5 minutes = 300 seconds, and the distance traveled is unknown. So we have:

d1 = 0 + 1/2 * a * (300)^2

For the second phase of constant speed, the initial velocity is v, the time is 5 minutes = 300 seconds, and the distance traveled is also unknown. So we have:

d2 = v * 300

For the third phase of deceleration, the initial velocity is v, the time is also 5 minutes = 300 seconds, and the distance traveled is again unknown. So we have:

d3 = v * 300 + 1/2 * (-a) * (300)^2

The total distance traveled is the sum of these three distances:

distance = d1 + d2 + d3 = 1/2 * a * (300)^2 + v * 600 - 1/2 * a * (300)^2 = v * 600

Since the total distance traveled is given as 10 km = 10000 m, we have:

v * 600 = 10000

Solving for v, we get:

v = 10000/600 = 50/3 m/s

Now we can use the second equation above to find a:

d2 = v * 300 = (50/3) * 300 = 5000 m

Therefore, the constant acceleration of the train is:

a = 2 * (5000 - 1/2 * a * (300)^2) / (300)^2 = 50/9 m/s^2

The constant acceleration of the train is 50/9 m/s^2.

Problem 2: The height of the first ball dropped is given as 10m. Let's assume the height of the collision point is h meters above the ground.

Using the kinematic equation for free fall, we have:

h = 10 + 1/2 * g * t^2

where g is the acceleration due to gravity, which is approximately 9.81 m/s^2, and t is the time it takes for the second ball to reach the collision point after being thrown upwards.

The initial upward velocity of the second ball is 10 m/s, and we know that at the collision point, its velocity will be zero, since it will have reached its maximum height and will be momentarily at rest before falling back down.

Using the kinematic equation for motion with constant acceleration, we have:

0 = 10 + (-g) * t

Solving for t, we get:

t = 10/g = 10/9.81 seconds

Substituting this value of t into the first equation, we get:

h = 10 + 1/2 * 9.81 * (10/9.81)^2

Simplifying, we get:

h = 10.204 m

The two balls will collide at a height of approximately 10.204 meters above the ground.

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Related Questions

is the equation a=v^2/r dimensionally correct?

Answers

Answer:

No, the equation a=v^2/r is not dimensionally correct. This can be seen by breaking down the dimensions of each term in the equation.

The dimension of acceleration (a) is length/time^2 (L/T^2).

The dimension of velocity (v) is length/time (L/T).

The dimension of radius (r) is length (L).

Substituting these dimensions into the equation, we get:

L/T^2 = (L/T)^2 / L

Simplifying this expression, we get:

L/T^2 = L/T^2

This means that the dimensions on both sides of the equation are equal and therefore the equation is dimensionally correct.

Answer:

Yes, the equation a=v^2/r is dimensionally correct.

Explanation:

The dimensions of acceleration (a) are distance/time^2, the dimensions of velocity (v) are distance/time, and the dimensions of radius (r) are distance.

When we substitute these dimensions into the equation a=v^2/r, we get:

a = (distance/time)^2 / distance

Simplifying, we get:

a = distance^2 / time^2 / distance

a = 1 / time^2

Therefore, the dimensions of both sides of the equation are the same, which confirms that the equation is dimensionally correct.

true/false.if you were standing directly at the earth's north magnetic pole, in what directino would a compass point if it were free to swivel in any direction

Answers

True. The compass would point south, towards the Magnetic South Pole, if it were free to swivel in any direction.

If you were standing directly at the Earth's North Magnetic Pole, a compass would point towards the Magnetic South Pole. A compass is a simple instrument used to determine direction. It is based on the principle that Earth has a magnetic field that attracts certain metals, such as iron. The needle on a compass is a small magnet that is suspended so that it can rotate freely. When the compass is held level, the needle is able to rotate until it comes to rest along the magnetic lines of force, indicating the direction of the magnetic north. However, the magnetic North Pole is not the same as the geographic North Pole, which is the point where the Earth's axis of rotation intersects with the surface of the planet.

The Earth's magnetic field is generated by the motion of molten iron in the outer core. As a result, the magnetic field is not perfectly aligned with the axis of rotation. It is tilted at an angle of approximately 11.5 degrees. This means that the magnetic North Pole is not located at the same point as the geographic North Pole. If you were standing directly at the Earth's North Magnetic Pole, a compass would point towards the Magnetic South Pole. This is because the North and South Poles of a magnet are opposite. When the north-seeking pole of a compass needle is placed near the North Magnetic Pole, it will be attracted to the south-seeking pole of the Earth's magnetic field, which is located in the vicinity of the Magnetic South Pole.

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a tennis ball is dropped from a height of 1.21 m above the ground. calcualte its velocity when it is 0.27m from the ground

Answers

The velocity of the tennis ball when it is 0.27m from the ground is approximately 3.39 m/s.

What is velocity?

To calculate the velocity of the tennis ball when it is 0.27m from the ground, we can use the principle of conservation of mechanical energy, which states that the total mechanical energy of an object is conserved when it moves through a conservative force field, such as gravity.

At the initial position, the ball has potential energy due to its position above the ground, but no kinetic energy as it is at rest. At the final position, the ball has no potential energy (since it is at the same height as the ground), but it has kinetic energy due to its motion. Assuming that air resistance is negligible, the initial potential energy is converted into final kinetic energy, so we can equate these energies:

mgh = (1/2)mv²

where m is the mass of the ball, g is the acceleration due to gravity, h is the initial height of the ball above the ground, and v is the velocity of the ball when it is 0.27m from the ground.

We can rearrange this equation to solve for v:

v = √(2gh)

Substituting the given values, we get:

v = √(2 x 9.81 m/s² x (1.21 m - 0.27 m)) = 3.39 m/s

Therefore, the velocity of the tennis ball when it is 0.27m from the ground is approximately 3.39 m/s.

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by how much should lower the pressure at the top of the straw to have the lemonade rise 5 cm above the surface

Answers

The lemonade rise 5 cm above the surface, you must lower the pressure at the top of the straw by [tex]49 N/m^2[/tex] (or Pascals).

Let's assume that atmospheric pressure is 1 atm, and we want to raise the water to a height of 5 cm. Pressure in a fluid increases with depth, and the pressure at the bottom of the fluid is greater than the pressure at the top. Consider a horizontal straw filled with water that is open at both ends.

The pressure of the water in the straw is determined by atmospheric pressure at the open end of the straw. At the bottom of the straw, the pressure is the same as the pressure of the surrounding water (P0).

Let us consider a horizontal straw in which the water level rises to a height of 5 cm above the surrounding water when the pressure at the top of the straw is lowered by an amount of P.

As a result, the pressure of the water at the top of the straw is now (P + 1 atm), and the pressure at the bottom of the straw is (P0 + P).

Because the pressure at the bottom of the straw (P0 + P) is equal to the pressure of the surrounding water (P0), we have:

P0 + P = P0 + ρgh.

Solving for P, we get:

P = ρgh

In this case, h = 5 cm,

ρ is the density of lemonade, and

g is the acceleration due to gravity.

The value of g is [tex]9.8 m/s^2[/tex] on average.

[tex]ρgh = (1000 kg/m^3) × (9.8 m/s^2) × (0.05 m) = 49 N/m^2[/tex] (or Pascals).

So, to have the lemonade rise 5 cm above the surface, you must lower the pressure at the top of the straw by [tex]49 N/m^2[/tex] (or Pascals).

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P2. Charges q and Q are placed on the x-y plane at (0,0) and at (0, 3) m, respectively.
Where q = 50 pC and Q = -40 pC.
a. Draw the situation to solve the next step.
b. Determine the net electric flux through a closed cylindrical surface that has a diameter of 5 ma
a height of 4 m, where the axis of the cylinder is the z axis and its mid-point is at the origin.

Answers

(a). Here is a diagram of the situation:

        |           Q (-40 pC)

        |             ^

        |             |

 --------|----------- 3 m

        |             |

        |             |

        |             |

        |             |

        |             |

        |           q (50 pC)

        |_____________|___________> x = 0 m

            3 m

(b).  The net electric flux through the closed cylindrical surface is -100.5 N m^2/C.

We can use Gauss's Law to calculate the electric flux through the cylindrical surface.

Choose a cylindrical Gaussian surface of radius r=2.5 m and height h=4 m, centered at the origin.The electric field at any point on the cylindrical surface due to Q is given by E_Q = kQ/r^2, where k is Coulomb's constant (9 x 10^9 N m^2/C^2).The electric field at any point on the cylindrical surface due to q is given by E_q = kq/r^2.The net electric field at any point on the cylindrical surface is E_net = E_Q + E_q.Since the surface is symmetric around the z-axis, we can assume that the electric field is perpendicular to the end surfaces of the cylinder, so the electric flux through these surfaces is zero.Therefore, the net electric flux through the cylindrical surface is Φ_E = E_net * A, where A is the area of the curved surface of the cylinder.The area of the curved surface of the cylinder is A = 2πrh = 20π m^2.Substituting the values for E_Q and E_q, we get E_net = -1.60 x 10^6 N/C (negative because the electric field due to Q is in the opposite direction to that due to q).Therefore, Φ_E = (-1.60 x 10^6 N/C) * (20π m^2) = -100.5 x 10^6 N m^2/C = -100.5 N m^2/C.

Therefore, the net electric flux through the closed cylindrical surface is -100.5 N m^2/C.

What is an electric flux?

Electric flux is the measure of the total electric field passing through a surface. It is a scalar quantity, and its unit is the volt meter (V m) or newton meter squared per coulomb (N m^2/C).

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In the circuit in the figure, a 20-ohm resistor sits inside 104 g of pure water that is surrounded by insulating Styrofoam.
If the water is initially at temperature 11.8 C, how long will it take for its temperature to rise to 57.1 C?
Use 4190 J/kg.C as the heat capacity of water, and express your answer in seconds using three significant figures.

Answers

The time taken for the water to raise its temperature from 11.8[tex]C^o[/tex] to 57.1[tex]C^o[/tex] is 987 s.

[tex]t = \frac{mc(\theta_1 - \theta_2)}{I^2R_1}\\= \frac{(0.104kg)(4190/kg.C^o [(5.71C^o) - (11.8C^o)])}{(1.0A)^2(20.0)}[/tex]

=987s

Temperature is a measure of the average kinetic energy of the particles in a substance or system. In simpler terms, it is a way of measuring how hot or cold something is. The unit of measurement for temperature is typically degrees Celsius (°C) or Fahrenheit (°F), although other units such as Kelvin (K) may also be used.

Temperature plays a critical role in many physical and chemical processes, from the behavior of gases to the functioning of the human body. In general, higher temperatures increase the speed of molecular motion, leading to faster reactions, greater energy transfer, and increased expansion or contraction of materials. Lower temperatures, on the other hand, tend to slow down molecular motion and decrease reaction rates, energy transfer, and material expansion.

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1.- What is net net charge on the sweater? Why?
2.- What is the net charge on the balloon? Why?

ASAP pls and thank you!!

Answers

When students brush balloons against their wool sweaters or hair, electrons are moved from the wool or hair to the balloon. As a result, the balloon has a net negative charge, whereas the garment or hair, having shed negative charges, has a net positive charge.

What is net charge?

The term "net" refers to the sum after both positive and negative costs have been deducted. So, if something has 321 positive charges and 319 negative charges, the overall charge is 321 - 319 = +2. The overall charge is 37 - 42 = -5 if it includes 37 positive charges and 42 negative charges.

Electrons are negatively charged, whereas protons are favourably charged. Atoms have an identical amount of electrons and protons and have a net charge of zero. This makes atoms always neutral.

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a 504 g mass oscillates with an amplitude of 12.0 cm on a spring whose spring constant is 20.0 n/m .

Answers

The period of oscillation is approximately 0.998 seconds.

Steps

We can use the following formula to find the period of oscillation:

T = 2π√(m/k)

where T is the period, m is the mass, and k is the spring constant.

Substituting the given values, we get:

T = 2π√(0.504 kg / 20.0 N/m)

T = 2π√(0.0252 kg/m)

T = 2π * 0.1589 s

T = 0.998 s (rounded to three significant figures)

Therefore, the period of oscillation is approximately 0.998 seconds.

The force needed to stretch or compress a spring by a specific amount is known as the spring constant (k), which serves as a gauge for a spring's stiffness. In the SI system, the spring constant is measured in Newtons per meter (N/m).

For example, if a spring requires a force of 10 N to stretch it by 0.5 meters, then the spring constant is:

k = F/x = 10 N / 0.5 m = 20 N/m

In many computations involving elastic systems, such as the oscillation of a mass on a spring or the compression of a spring in a mechanical system, the spring constant, a crucial spring parameter, is taken into account.

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What is the magnitude of the total charge of all the electrons in 2.6 L
of liquid water?

Answers

The total charge of all electrons in 2.1 liters of liquid water would be zero as the number of electrons and protons in a neutral sample of water are equal

a motor uses kn of force to power a vehicle that has a top speed of m/s. what is the power delivered by the motor? round answers to one decimal place.

Answers

A motor uses kn of force to power a vehicle that has a top speed of m/s. The power delivered by the motor is 9.8 kW (kilowatts).

To compute the power delivered by the motor, use the following formula:

P = Fv

Where:

P is the power delivered by the motor

F is the force exerted by the motor

v is the velocity at which the motor delivers the force

First, convert the force from kN to N by multiplying it by 1000 kN = 1000 N.

Now we can substitute the values in the formula:

P = 1000 N × m/sP = 1000 Nm/s

To convert Newton-meter to watts, divide it by the conversion factor 1 W = 1 J/s.

So:P = 1000 Nm/s / 1 WP = 1000 W

To convert watts to kilowatts, divide it by 1000. So:

P = 1000 W / 1000P = 1 kW

The power delivered by the motor is 1 kW.

Rounding it to one decimal place:

P = 1.0 kW

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5. In the diagram below, Aircraft A is flying East and maintaining a groundspeed of 340 kt (a kt = speed of 1 NM / hr). Aircraft B is flying in the same direction as aircraft A but 210 NM ahead, maintaining a ground speed of 280 kt. Aircraft A will catch Aircraft B at Point ‘X’. What distance will Aircraft B have travelled when this event occurs?

Answers

Aircraft B will have travelled 980 NM when it is caught up by Aircraft A.

We can begin by using the formula:

distance = rate × time

Let's first find the time it will take for Aircraft A to catch up with Aircraft B. Since both are flying in the same direction, the relative speed between them will be the difference in their ground speeds:

relative speed = ground speed of A - ground speed of B

= 340 kt - 280 kt

= 60 kt

The distance between the two aircraft is 210 NM. Using the relative speed, we can find the time it will take for Aircraft A to catch up to Aircraft B:

time = distance / relative speed

= 210 NM / 60 kt

= 3.5 hours

Now, we can find how far Aircraft B will have travelled in 3.5 hours at its own ground speed of 280 kt:

distance = rate × time

= 280 kt × 3.5 hours

= 980 NM

Therefore, Aircraft B will have travelled 980 NM when it is caught up by Aircraft A.

What is an aircraft?

An aircraft is a machine that is designed to be able to fly through the air. It typically has fixed or rotary wings, and is powered by engines or other propulsion systems. Aircraft come in a wide variety of shapes and sizes, from small, single-engine planes to large commercial airliners and military aircraft.

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which of the following would have the strongest magnetic field. assume the current in each is the same

Answers

Answer: Neodymium

Explanation: Neodymium is the strongest magnet. It is an alloy made from iron and boron. is the strongest magnet.

The strength of the magnetic field around the coil can be increased by increasing the current flowing through the coil (this will increase the flux) or by increasing the number of coil turns. which will also increase the flux Φ.

at the poles

The magnetic field around a magnet is the strongest at the poles. The maximum number of magnetic field lines pass through the poles.

Difference between capillary action and siphoning action?

Answers

Explanation:

Capillary action and siphoning action are two different phenomena that involve the movement of fluids, but they work in different ways.

Capillary action refers to the movement of a liquid along a narrow tube or capillary due to the adhesive and cohesive properties of the liquid. This happens because the liquid molecules are attracted to the walls of the capillary, which creates a meniscus that draws the liquid up the tube. The height that the liquid rises in the capillary depends on the surface tension and the diameter of the capillary.

Siphoning action, on the other hand, is the movement of a liquid from a higher point to a lower point through a tube or hose. This happens due to the force of gravity and the difference in pressure between the two ends of the tube. The liquid flows from the higher end to the lower end because of the pressure difference, with atmospheric pressure pushing the liquid up the tube on the higher end and gravity pulling it down on the lower end.

Explanation:

Capillary action and siphoning action are both related to the movement of fluids, but they differ in their mechanisms and applications.

Capillary action refers to the ability of a liquid to flow in narrow spaces or tubes, such as capillary tubes or small pores. This is due to the cohesive forces between the liquid molecules, which cause them to adhere to the walls of the container and rise up the tube. The thinner the tube, the higher the liquid can rise. Capillary action is responsible for many natural phenomena, such as the movement of water through plants and the formation of meniscus in a test tube.

On the other hand, siphoning action refers to the transfer of a liquid from one container to another by means of a tube. This is due to the difference in pressure between the two containers, which causes the liquid to flow from the higher container to the lower container through the tube. Siphoning action can be initiated by creating a vacuum in the tube, either by sucking on it or by using a pump. Siphoning action is often used in practical applications, such as transferring fuel or other liquids from one container to another.

In summary, capillary action is the movement of a liquid within a confined space due to cohesive forces, while siphoning action is the transfer of a liquid from one container to another due to pressure differences.

This hair-dryer has a plastic case. It is connected to a mains socket by a 3-pin plug.
The cable connecting the hair-dryer to the plug contains only two wires.
Write down the colour of the insulation on the wires.
Wire 1
Wire 2
(ii)
Which of the usual three wires is not needed?
=
This hair-dryer is safe to use without the third wire. Explain why.

Answers

Wire 1 and Wire 2 are typically insulated with one of three standard colors: black, white, or red.

The wire that is not needed is the earth wire, which is typically green or yellow with green stripes. The earth wire is used for safety purposes to provide a path for current to flow to the ground in case of a fault or short circuit, but is not strictly necessary for the operation of the hair-dryer.

The hair-dryer is safe to use without the earth wire because it is double-insulated. This means that the hair-dryer has two layers of insulation between the live and neutral wires and the outer casing, which provides an extra level of protection against electrical shocks. Double-insulated appliances are designed to operate safely without the need for an earth wire, and are marked with a symbol consisting of a square inside another square to indicate this.

What is an earth wire?

An earth wire, also known as a ground wire or protective earth (PE) wire, is a safety wire used in electrical wiring systems. It is designed to provide a path for electrical current to flow to the ground in the event of an electrical fault, such as a short circuit or a surge.

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If the pressure exerted on the floor by a box is 200kpa, find the weight of the box given that the bottom of the box has a contact area of 20cm³?​

Answers

Basically the pressure times area gives the force applies by the box on the floor which is its weight.
So, F = 2 x 20 x 10^5 x 10^-6 N = 4N
So the weight is 4 Newtons

The weight of the box is approximately 0.0408 kg.

What is Pressure?

Pressure is a measure of how much force is applied per unit area of surface. It is a scalar quantity and has units of force per unit area. It is typically expressed in units such as pascals (Pa), atmospheres (atm), or pounds per square inch (psi).

We can use the formula:

pressure = force / area

where pressure is given as 200 kPa and area is given as 20 cm^2. Converting cm^2 to m^2:

20 cm^2 = 20 x 10^-4 m^2 = 0.002 m^2

Substituting the values in the formula and solving for force:

200 kPa = force / 0.002 m^2

force = 200 kPa x 0.002 m^2

force = 0.4 kN (kilonewtons)

The weight of the box is the force acting on it due to gravity, which is given by:

weight = mass x gravitational acceleration

Assuming the box is on the Earth's surface, we can use a value of 9.81 m/s^2 for gravitational acceleration. Solving for mass:

mass = weight / gravitational acceleration

mass = 0.4 kN / 9.81 m/s^2

mass = 0.0408 kg (kilograms)

Therefore, the weight of the box is approximately 0.0408 kg.

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A ski resort can manufacture enough machine made snow in 4 h to open its steepest run, whereas it would take 12 h of naturally falling snow to provide enough snow. If the resort makes snow while it is snowing naturally, how long (in h) will it take until the run can open?

Answers

The run will be able to open in 4 hours when machine-made snow is produced while it is snowing naturally.

Let the rate of production of machine-made snow be m units/hour, and the rate of snowfall be n units/hour. From the given information, we know that:

m × 4 = n × 12 => m/n = 3/1

Let the time taken for the run to open when both types of snow are produced simultaneously be t hours.

In that time, the ski resort will have produced mt units of machine-made snow and nt units of naturally falling snow.

We also know that mt + nt is equal to the amount of snow required to open the run. Therefore:

mt + nt = m × 4 => nt = m(4 - t) (1) and

mt + nt = n × t => mt = n(t - 12) (2)

Substituting the value of m/n obtained above in (1), we have:

nt = 3n(4 - t) => nt = 12n - 3nt => nt = 6n (3)

Substituting the value of mt obtained above in (2), we have:

n(t - 12) = 3nt => t = 4 hours

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Problem 3 For the shaft below, calculate factors of safety based on the distortion energy theory for stress elements A and B when F 0.55 kN, P 4 kN, and T = 25 N.m. The shaft is made of AISI 1006 cold-drawn (CD) steel 15-mm D

Answers

The factor of safety based on the distortion energy theory for stress elements A and B of the shaft when F = 0.55 kN, P = 4 kN, and T = 25 N.m and made of AISI 1006 cold-drawn (CD) steel 15-mm D is 66.67 and 26.66, respectively.

The factor of safety based on the distortion energy theory for stress elements A and B of the shaft when F = 0.55 kN, P = 4 kN, and T = 25 N.m and made of AISI 1006 cold-drawn (CD) steel 15-mm D can be calculated as follows:

For stress element A:

Factor of Safety = [tex](2τ_allowable\times L)/(F\times d)[/tex]

Where τ_allowable is the allowable shear stress for the material, L is the length of the element, F is the force acting on the element, and d is the diameter of the element.

For this example, τ_allowable = 55 MPa (from AISI 1006 CD steel data), L = 0.15 m, F = 0.55 kN, and d = 0.015 m.

Therefore, Factor of Safety = [tex](2 \times 55 \times 0.15) / (0.55 \times 0.015) = 66.67[/tex]

For stress element B:

Factor of Safety =[tex](τ_allowable\times L^2)/(T\times d^3)[/tex]

Where τ_allowable is the allowable shear stress for the material, L is the length of the element, T is the torque acting on the element, and d is the diameter of the element.

For this example, τ_allowable = 55 MPa (from AISI 1006 CD steel data), L = 0.15 m, T = 25 N.m, and d = 0.015 m.

Therefore, Factor of Safety =[tex](55 \times 0.15^2) / (25 \times 0.015^3) = 26.66[/tex]

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fter sailing 12 mi, a sailor changed direction and increased the boat's speed by 2 mph. An additional 15 mi was sailed at the increased speed. The total sailing time was 3 h. Find the rate of the boat for the first 12 mi.

Answers

The rate of the boat for the first 12 miles is 24/13 mph.

After sailing 12 miles, a sailor changed direction and increased the boat's speed by 2 mph. An additional 15 miles was sailed at the increased speed. The total sailing time was 3 hours.

We need to find the rate of the boat for the first 12 miles.Let the rate of the boat for the first 12 miles be r mph. Therefore, the speed of the boat after the change of direction is (r + 2) mph.

Distance covered in the first 12 miles = 12 miles

Time taken for the first 12 miles = 12/r

Distance covered in the next 15 miles = 15 miles

Time taken for the next 15 miles = 15/(r + 2)

Total time taken = 3 hours

Therefore,12/r + 15/(r + 2) = 3

Multiply the above equation by r(r + 2), we get:

12(r + 2) + 15r = 3r(r + 2)

Simplify and solve for r:

r = 24/13 mph

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when a ray of light hits a surface, the angles made by the reflection and refraction of the ray must all be measured from the normal, which is

Answers

When a ray of light hits a surface, the angles made by the reflection and refraction of the ray must all be measured from the normal, which is perpendicular to the surface at the point where the light ray hits it.

Reflection occurs when light rays hit a surface and bounce back whereas Refraction, occurs when light travels through a medium of a different density or refractive index.

The laws of reflection and refraction states that the angle of incidence is equal to the angle of reflection, and the ratio of the sine of the angle of incidence to the sine of the angle of refraction is constant. This ratio is known as the refractive index of the material from where the light is passing through.

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Question 1
11) You are driving a vehicle at 55 mph on dry pavement, about how much total stopping distance do you need
to bring it to a stop?

Answers

The total stopping distance required to bring it to a stop is 300 metres.

What exactly is stopping distance?

The stopping distance is the distance travelled between the time a moving vehicle's body decides to stop and the time the vehicle completely stops.

Bringing a moving vehicle to a stop involves three critical factors.

1.Distance of perception

2. Distance between reactions

3.Distance between the brakes

1. Perception distance is the amount of time that a vehicle travels while your brain perceives the need to apply the brakes.

An alert driver must react in about 0.75 seconds. This time represents approximately 60 feet of travel.

2. Reaction distance is the distance travelled before the driver applies the brakes. This takes about 0.75 seconds for a cautious

driver. This adds an additional 60 feet of travel.

3. Braking distance is the distance travelled by a vehicle before coming to a complete stop on dry ground. This distance is longer on slick ground (after snow or rain). The skidding distance on dry ground is approximately 170 feet.

This means that a cautious driver needs 60+60+170 = 290 feet (approximately 300 feet) to come to a complete stop.

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Determine the magnitude of force at the pin A and in the cable BC needed to support the 500-lb load. Neglect the weight of the boom AB

Answers

The magnitude of the force at pin A and in cable BC needed to support the 500-lb load is 2,000 lbs, since the cable BC supports 1/4 of the load. The force in the cable is transferred to the pin A and distributed along the boom AB. The weight of the boom AB can be neglected in this calculation.

Load = 500 lb Boom AB = Neglected To determine :Magnitude of force at the pin A and in the cable BC needed to support the 500-lb load Formula used:ΣFx = 0ΣFy = 0

Considering point AΣFy = 0ΣFy = Ay - 500Ay = 500 lb Considering point CΣFx = 0∴T cos 45° = 0T = 0 lbΣFy = 0∴T sin 45° - B = 0B = T sin 45°B = T / √2By substituting the value of T in the above equation we get B = 0 lb Therefore, force required at pin A is 500 lb and force required in the cable BC is 0 lb to support the 500-lb load.

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Which of the following techniques is the key factor in a telescope that uses adaptive optics to correct for atmospheric distortion of images, or seeing? O Computer-controlled motors rapidly adjust the orientation and position of the separate primary mirrors in a multiple-mirror telescope (MMT). O A corrector lens compensates for image distortion by electronic control of its shape. O Computer-controlled motors adjust the position and shape of one of the small mirrors within the optics many times per second. The light rays are focused electronically, without the use of lenses or mirrors.

Answers

The technique that is the key factor in a telescope that uses adaptive optics to correct for atmospheric distortion of images, or seeing is: Computer-controlled motors adjust the position and shape of one of the small mirrors within the optics many times per second.

Adaptive optics is a technology used to improve the performance of optical systems by reducing the effect of wavefront distortions by adjusting for distortions in real-time. Adaptive optics compensate for these distortions by removing the wavefront distortion from the incoming light and returning an undistorted image to the detector. This technique is especially helpful for telescopes that use optics to observe astronomical objects.

In a telescope, Adaptive optics involves two main components:

a wavefront sensor and a wavefront corrector. The wavefront sensor measures the wavefront distortion and sends this information to the wavefront corrector, which changes its shape to correct for the distortion.The technique that is the key factor in a telescope that uses adaptive optics to correct for atmospheric distortion of images, or seeing is Computer-controlled motors adjust the position and shape of one of the small mirrors within the optics many times per second.

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Eating disorders that go untreated can lead to serious illness, unhappiness, depression, and even death.

A.
True

B.
False

Answers

A. Eating disorders that go untreated can lead to serious illness, unhappiness, depression, and even death is True.

Eating disorders such as anorexia, bulimia, and binge-eating disorder can have serious psychological consequences if left untreated.

What is depression?

Depression is a mental health disorder characterized by persistent feelings of sadness, hopelessness, and a loss of interest in activities that were once enjoyable. It can affect a person's thoughts, emotions, behavior, and overall physical well-being.

What is anorexia?

Anorexia, also known as anorexia nervosa, is a serious eating disorder characterized by a persistent restriction of food intake, an intense fear of gaining weight, and a distorted body image. People with anorexia often have an extremely low body weight and may engage in behaviors such as excessive exercise, the use of laxatives to lose weight.

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Complete question is: Eating disorders that go untreated can lead to serious illness, unhappiness, depression, and even death is True.

Complete the following statement: The polarization direction of an electromagnetic wave is determined by the wavelength of the electromagnetic radiation. the direction of the magnetic field component the direction of the electric field component the direction the wave is traveling. the frequency of the electromagnetic radiation.

Answers

The polarization direction of an electromagnetic wave is determined by the direction of the electric field component.

What is an electric field ?

Electromagnetic waves consist of oscillating electric and magnetic fields that are perpendicular to each other and to the direction of the wave's propagation. The direction of the electric field component determines the polarization direction of the wave. The electric field component oscillates perpendicular to the direction of propagation and determines the orientation of the electromagnetic wave.

In contrast, the wavelength, frequency, and direction of travel of the electromagnetic wave do not affect the polarization direction of the wave. However, the wavelength and frequency of the wave are related to its energy and momentum.

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Complete statement is: The polarization direction of an electromagnetic wave is determined by the direction of the electric field component.

Please help 50 points and Brainly

Answers

Mechanical energy Electrical energyThermal energy

What is mechanical energy?

Mechanical energy is the energy possessed by an object due to its motion or position. It is the sum of kinetic energy and potential energy of an object, which can be converted to other forms of energy, such as electrical energy or thermal energy.

What is electrical energy?

Electrical energy is the energy associated with the movement of electrons through a conductor or an electrical circuit. It is the result of the movement of charged particles, such as electrons, and is commonly generated by the conversion of other forms of energy, such as mechanical, chemical, or solar energy.

What is thermal energy?

Thermal energy is the energy associated with the temperature of an object or a system. It is the result of the movement of atoms and molecules in matter, which leads to the transfer of heat from hotter to cooler objects. Thermal energy is commonly measured in units of joules or calories and is proportional to the mass and temperature of an object or a system.

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In the two-fragment explosion that results when a gun is fired, the bullet acquires a significantly higher speed compaired to the recoil speed of the gun. Use a physics formula or a physics principle (directly related to the observation) to justify the observation.

Answers

The bullet has a much smallar Mass, and in an explosion, the object with less mass will always achive the higher velocity due to conservation of momentum.

This can be proven simply by this equation.

[tex]M_1V_1i +M_2 V_2i = M_1V_1 + M_2 V_2.[/tex]

The only way for Momentum to be Conserved in this situation is for the lighter object to achive a higher velocity to overcome the farge mass of the other object which will unvariably have a Small Velocity.

Conservation of momentum is a fundamental principle in physics that states that the total momentum of a closed system remains constant if no external forces act upon it. In a closed system, any change in momentum of one object must be balanced by an equal and opposite change in momentum of another object within the system. This principle applies to both the linear and angular momentum of a system.

The conservation of momentum has broad implications in physics, ranging from the behavior of subatomic particles to the motion of planets in our solar system. It is particularly important in understanding collisions and explosions, where the total momentum of a system is conserved even if individual objects experience significant changes in momentum.

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Complete Question:-

In the two-fragment explosion that results when a gun is fired, the bullet acquires a significantly higher speed compaired to the recoil speed of the gun. Use a physics formula or a physics principle (directly related to the observation) to justify the observation.

5.32 calculate ix and vo in the circuit of fig. 5.70. find the power dissipated by the 60-k resisto

Answers

The power dissipated by the 60-k Ohm resistor is 3 mv and 24mv.

[tex]=V_1=V =4mv\\=I_{iN}=\frac{4mv}{10k}=0.4\mu A\\= \frac{V_1 - V+}{50k}=0.4\mu A\\V_1 - 4m= 20m\\V_1 = 24mv[/tex]

[tex]i_x=\frac{V_1}{20+(6 || 3)} =\frac{24*10^{-3}}{(20+2.857)*10^{3}}\\i_x=1.05\mu A\\i_0=\frac{i_x*60}{60+3}=1\mu A\\V_0=3k*1\mu=3mv\\V_0=3mv[/tex]

An Ohm resistor is a passive electrical component that restricts the flow of current in an electrical circuit. It is named after Georg Simon Ohm, a German physicist who discovered Ohm's law which states that the current flowing through a conductor between two points is directly proportional to the voltage across the two points.

An Ohm resistor has a resistance value measured in ohms, which determines how much it restricts the flow of current. The higher the resistance value, the more it restricts the current flow. Ohm resistors are commonly used in electronic circuits to control the voltage and current levels, and to protect sensitive electronic components from damage. They can also be used to divide voltages, as voltage dividers, or as current limiting devices.

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Complete Question: -

Calculate i_x and v_o in the circuit of Fig. 5.70. Find the power dissipated by the 60-k Ohm resistor.

An applied frictional force on this wheel (not shown) causes it to slow down until it comes to a complete stop after a time interval Δt, where: |ωo| = 34.28 rad/s, R = 0.29 m, |α| = 1.77 rad/s2.

a) Solve for the time interval needed for the wheel to come to a complete stop.

19.37s

b) Solve for total angular distance traveled (in radians, not meters) by the wheel during this time interval.

Answers

We can use the formula for angular deceleration to find the time interval needed for the wheel to come to a complete stop:

α = (ωf - ωo) / Δt

where ωf is the final angular velocity, ωo is the initial angular velocity, and Δt is the time interval. Rearranging the formula, we get:

Δt = (ωf - ωo) / α

Since the wheel comes to a complete stop, the final angular velocity is zero:

ωf = 0

Substituting the given values, we get:

Δt = (0 - 34.28) / (-1.77) ≈ 19.37 s

What is the r total angular distance traveled?

The formula for angular displacement is:

θ = ωo t + (1/2) α t^2

where θ is the angular displacement, ωo is the initial angular velocity, α is the angular acceleration, and t is the time interval. When the wheel comes to a complete stop, the final angular velocity is zero, so the formula simplifies to:

θ = ωo t + (1/2) α t^2

Substituting the given values, we get:

θ = (34.28 rad/s)(19.37 s) + (1/2)(-1.77 rad/s^2)(19.37 s)^2 ≈ -2003.9 rad

The negative sign indicates that the wheel has rotated in the opposite direction of its initial motion.

To get the total angular distance traveled by the wheel during this time interval, we take the absolute value of θ:

|θ| = |-2003.9 rad| = 2003.9 rad

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Two identical projectiles are fired at the same time. Projectile A has a speed of 300m/s and projectile B has a speed of 600m/s. What is the ratio of the Kinetic Energy of projectile B to projectile A?

Answers

The ratio of the kinetic energy of projectile B to projectile A is 4:1.

The kinetic energy (KE) of an object is given by the formula

KE = 1/2 * m * v^2

where m is the mass of the object and v is its velocity.

Assuming the two projectiles have the same mass, we can compare their kinetic energies based solely on their velocities:

KE_B/KE_A = (1/2 * m * v_B^2)/(1/2 * m * v_A^2)

= (v_B^2/v_A^2)

Substituting the values given in the problem:

KE_B/KE_A = (600 m/s)^2 / (300 m/s)^2

= 4

Therefore, the ratio of the kinetic energy of projectile B to projectile A is 4:1. Projectile B has four times the kinetic energy of projectile A.

What is kinetic energy?

Kinetic energy is the energy an object possesses by virtue of its motion. It is a scalar quantity that depends on the mass and velocity of the object.

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If pulse 1 were reflected from a wall, which one of the patterns above would represent the reflected pulse? A) 1 B) 2 C) 3 D) 4 E) 5

Answers

If pulse 1 is reflected from a wall, pattern 2 would represent the reflected pulse. This is because when a wave is reflected from a fixed end, its amplitude is inverted. So, pattern 2 represents the reflection of pulse 1 from a fixed end.

A pulse is a short burst of energy that travels through space or matter. These bursts of energy can come in many different forms, including sound waves, light waves, and even electromagnetic radiation. In the context of waves, a pulse refers to a single disturbance that propagates through a medium. The reflection of waves refers to the behavior of waves that encounter a barrier or a discontinuity in a medium that causes them to return to their original medium. When waves are reflected, their direction of motion changes, and they experience a change in amplitude, phase, and polarization.

The amplitude of the reflected wave is related to the amplitude of the incident wave, as well as to the reflectivity of the medium. The reflection of waves is an essential phenomenon in many fields of science and engineering. For example, it is essential in optics, where it is used to form images in mirrors and lenses. It is also important in acoustics, where it is used to analyze the characteristics of sound waves. In addition, the reflection of waves is a critical aspect of the design of structures such as bridges and buildings, where it can help to reduce the impact of seismic waves during an earthquake.

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