The minimum furnace output for a 1600-ft² modern house is 464000 BTUs.
What is BTU?British thermal units (Btu) are a unit used to measure the amount of heat in fuels or other energy sources. The amount of heat needed to raise a pound of liquid water's temperature by one degree Fahrenheit at the point where water has its highest density (approximately 39 degrees Fahrenheit).
The formula: the minimum furnace output, B = 29 a.
Area of modern house = 1600 ft²
The minimum furnace output = 29×16000 BTUs
= 464000 BTUs.
Hence, the minimum furnace output for a 1600-ft² modern house is 464000 BTUs.
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A block moving at a velocity of 18 m/s along a frictionless surface encounters a rough area with which it does have a coefficient of friction. It moves along this rough area for 30 meters before slowing to a speed of 6 m/s. Find the coefficient of kinetic friction between the block and this rough surface.
The coefficient of kinetic friction between the block and the rough surface is -0.6.
What is kinetic friction?Kinetic friction is a type of friction that occurs when two objects are in contact and moving relative to each other. It is also known as sliding friction or dynamic friction. Kinetic friction is caused by the interaction of the two surfaces as they move against each other. The force of kinetic friction acts in the opposite direction of the motion of the two objects and is proportional to the normal force between them. The coefficient of kinetic friction is a measure of the amount of friction between two surfaces and is determined by the materials of the two surfaces.
The coefficient of kinetic friction can be found using the equation:
μk = (vf - vi) / (d * a)
where μk is the coefficient of kinetic friction, vf is the final velocity, vi is the initial velocity, d is the distance traveled, and a is the acceleration due to gravity (9.8 m/s2).
Plugging in the given values, we get:
μk = (6 - 18) / (30 * 9.8)
μk = -0.6
Therefore, the coefficient of kinetic friction between the block and the rough surface is -0.6.
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Write two or three sentences to describe the conductivity of a conductor. Explain its conductivity in terms of the electrons in it.
The conductivity of a conductor refers to its ability to conduct electrical current.
A material that has high conductivity allows electrical charges to flow through it easily and with little resistance, while a material with low conductivity does not allow electrical charges to flow as easily and has more resistance.
The conductivity of a conductor is determined by the number of free electrons in the material, as well as how easily these electrons can move through the material.
In a conductor, the atoms are closely packed together and the electrons are not tightly bound to the atoms, allowing them to move freely through the material and carry an electrical charge. This facilitates the flow of electrical current through the material, resulting in high conductivity.
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For science class your teacher gives you and your partner a ball she ask you to figure out a way to Balance forces that you apply to the ball how do you partner show this?
Two forces are said to be balanced when their strengths are equal but their directions of action are opposing.
What is Balanced Force?The forces are balanced if the pullers are exerting equal force but going in the opposite direction on either side of the rope.
Forces that are balanced can cancel one another out. The thing stays in place whenever there is a balanced force.
To lift, turn, move, open, close, push, pull, and many other things requires forces. You apply force to a ball when you throw it in order for it to travel through the air. An object can be under the influence of multiple forces at once.
Therefore, Two forces are said to be balanced when their strengths are equal but their directions of action are opposing.
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A sample of copper (specific heat capacity of copper is 0.386J/g*C) absorbs 1200 J of heat and
the temperature of the water it is being heated in increases from 27*C to 95*C, what mass of
copper was heated?
The mass of copper heated from a temperature of 27°C to 95°C is 45.72 g.
What is mass?Mass is the quantity of matter contained in a body, The units of mass are
Kilogram (kg)Gram (g)Milligram (mg) etc.To calculate the mass of the copper, we use the formula below.
Formula:
m = Q/cΔt.................. Equation 1From the question,
Given:
m = MassQ = Amount of heatc = Specific heat capacity of copperΔt = Change in temperatureFrom the question,
Given:
Q = 1200 Jc = 0.386 J/g°CΔt = 95-27 = 68°Substitute these values into equation 1
m = 1200/(0.386×68)m = 45.72 gHence, the mass of copper is 45.72 g.
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19. A pitcher throws a baseball toward a batter at 30m/s. The batter swings his
bat and hits the baseball. The baseball flies away in the opposite direction at a
speed of 35m/s. Is there a transfer of energy in this situation? (SC.7.P.11.4)
a) Yes, because both the bat and the ball are moving after the collision.
b) No, because the ball and the bat only touched for a short time.
c) Yes, because the force from the bat changes the motion of the ball
A pitcher throws a baseball towards a batter at 30m/s. The batter swings his bat and hits the baseball, then there is a transfer of energy in this situation : c) Yes, because the force from the bat changes the motion of the ball.
How is energy transferred from baseball bat to a baseball?Although baseball may appear hard and solid, it actually behaves much like a rubber ball. In the fraction of a second that ball collides with the swinging bat, ball compresses as the energy of motion goes into deforming the ball and transforms it into an elastic potential energy.
The collision of baseball with bat is elastic and the collision between baseball and glove is nearly inelastic.
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Directions: Unscramble each word. Then write each term on the line before its definition.
1. antstonc
2. desep
3. ticlovey
4. onlacietrace
5. emincedsplat
6. tomoni
7. cenferree nitop
8. spooniti
9. measure of change in velocity
10. distance an object moves in a unit of time
11. change of position
12. distance and direction from a reference point
13. not changing
14. speed of an object in a given direction
15. distance between the initial and final position
16. starting point used to describe the location of an object
Answer:
constantspeedvelocityaccelerationdisplacementmotionreference pointpositionExplanation:
Above is the unscrambled words. Hope this helps!
The heaviest train ever pulled by a single engine was over 2 km long. Suppose a force of 1.13 X 10^8 N is needed to overcome static friction in the train's wheels. If the coefficient of static friction is 0.741, what's the train's mass?
The overcoming force is equal to the friction. The train's mass is 15,560,880.5 Kg
What is Friction ?Friction can simply be defined as a force that opposes the movement of an object in a plain surfaces.
Given that the heaviest train ever pulled by a single engine was over 2 km long. Suppose a force of 1.13 X 10^8 N is needed to overcome static friction in the train's wheels. If the coefficient of static friction is 0.741, what's the train's mass?
F = μN
Where
F = Frictional force = overcoming force = 1.13 X 10^8 Nμ = coefficient of static friction = 0.741N = Normal reaction = mgSubstitute all the necessary parameters
1.13 X 10^8 = 0.741N
N = 1.13 X 10^8/0.741
N = 152496626.2 N
N = mg
152496626.2 = 9.8m
m = 152496626.2/9.8
m = 15,560,880.5 Kg
Therefore, the mass of the train is 15,560,880.5 Kg.
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A particle which is moving in a straight line with a velocity of 15m/s accelerates uniformly for 3.0s, increasing its velocity to 45m/s. What distance does it travel while accelerating
The distance travel while accelerating is 90m
The initial velocity of the particle is 15m/s and the final velocity is 45m/s, so the change in velocity is 45m/s - 15m/s = 30m/s. The particle accelerates uniformly for 3.0s, so the acceleration is 30m/s / 3.0s >>30/3=10 that is 10m/s^2.
The distance traveled during the acceleration is equal to the average velocity times the time elapsed, so the distance traveled is (15m/s + 45m/s)/2 * 3.0s = (15+45)/2*3= 90m .
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In a particular crash test, an automobile of mass 1245 kg collides with a wall and bounces back off the wall. The x components of the initial and final speeds of the automobile are 18 m/s and 2.9 m/s, respectively. If the collision lasts for 0.11 s, find the magnitude of the impulse due to the collision. Answer in units of kg · m/s. Answer in units of kg · m/s.
Answer:
Δp=-18799.5kg*m/s
Explanation:
Δv=Vf-Vi
Δv=2.9m/s-18m/s
Δv=-15.1m/s
m*Δv=Δp
1245kg*(-15.1m/s)=Δp
Δp=-18799.5kg*m/s
Extra:
Deriving mΔv=Δp
Δp=Pf-Pi
Δp=m*Vf-m*Vi
Δp=m(Vf-Vi)
Vf-Vi=Δv
Δp=m(Δv) or Δp=mΔv
A lawnmower is pushed with a force of 72 Newtons at an angle of 40 degrees from the horizontal. How much work is done to the mower if it moves 740 meters?
The work done to the mower is the product of force and the distance covered by the object which is equal to 40,811 Joules.
What is Work done?Work done can be defined as the product of external force and the distance over which the force is being applied. Work is done on an object when a force is applied to an object and the object is moved through a particular distance.
From this we can see that:
X-Component:
cos(θ) = x/F
Then,
X= F cos(θ).…..(1)
Now putting the values of F and θ in equation (1) we get,
X = 72 N × cos(40)
X = 72 N × 0.766
X= 55.15 N this is the x-component force
The work done to the mower is:
W = F × d
W = 55.15 × 740
W = 40,811 Joules
The work done to the mower is 40811 Joules.
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Part A
What is the radius of the hydrogen-atom Bohr orbit shown in the figure? (Figure 1)
r = ____ nm
The radius of the hydrogen-atom Bohr orbit shown in the figure is 5.3 nm.
What is Bohr orbit?The path that hypothetical electrons take around the nucleus is known as Bohr's orbit.
These orbits are described by Bohr in his hypothesis of the structure of an atom as energy levels or shells where electrons move in a fixed circle around the nucleus.
These orbits resemble solar system orbits, with the exception that they are attracted by electrical forces rather than gravity. The term "ground state" refers to the amount of energy that an electron typically occupies.
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A box with a weight of 25N sits on the floor. What is the maximum force that could be applied horizontally on the box before it would start to accelerate if the coefficient of friction is 0.40?
So, we know that The box isn't moving at all. I'm assuming the coefficient they gave you is for static friction. We know that with static friction, the value that we calculate is a maximum value that represents the force we'd have to apply before an object starts moving!
We also know that the box isn't moving vertically. That means that its Y forces must be cancelling out, which means its weight force and its normal force must be equal to each other!
Now we can plug in these values into our static friction equation!
[tex]F_s[/tex] ≤ [tex]F_N[/tex] * μ[tex]_s[/tex]
[tex]F_s[/tex] ≤ (25N) (0.40)
[tex]F_s = 10[/tex]
Therefore your force that you'd need to apply is 10N!
n experimental vehicle starts from rest (0 = 0) at = 0 and accelerates at a rate given by
= (7m/s
3
). What is (a) its velocity and (2) its displacement 2 later?
The velocity of the experimental vehicle after 2 seconds is 14 m/s.
The displacement of the experimental vehicle after 2 seconds is 14 m.
What is the velocity and displacement of the experimental vehicle?The velocity of the experimental vehicle is the speed of the in a given direction starting from rest.
The velocity, v, of the experimental vehicle after 2 seconds is calculated using the formula below:
v = u + at
where;
u is the initial velocity = 0 m/s
a is the acceleration = 7 m/s²
t is time = 2 seconds
v = 0 + 7 * 2
v = 14 m/s
The displacement, s, of the vehicle is calculated below as follows:
v² = u² + 2as
14² = 0² + 2 * 7 * s
s = 196 / 14
s = 14 m
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Net work W would accelerate an object from rest to velocity v. What net work is needed to accelerate the object from rest to velocity 2v?
The net work that is needed to accelerate a 2.0 kg mass from rest to velocity 2v is 4.0 m/s.
What is net work done?When a force acts on a body at rest or at uniform motion in a straight line, then it starts to accelerate.
Given that, the velocity is 5.0
Time is 2 sec
The given mass is 2.0 kg
First, we calculate the acceleration
Acceleration = v / t = 10 / 5.0 = 2
From Newton's second law, we know that
force = mass x acceleration
F = ma
F = 2.0 x 2 = 4.0 m/s
Therefore, the net work that is needed to accelerate a 2.0 kg mass from rest to velocity 2v is 4.0 m/s.
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The question is incomplete. Your most probably complete question is given below:
What net force is needed to accelerate a 2.0 kg mass from rest to a velocity of 10 m/s in 5.0 s?
A model rocket flies horizontally off the edge of a cliff at a velocity of 50.0 m/s. If the canyon below is 100.0 m deep, how far from the edge of the cliff does the model rocket land?
My teacher provided the equations:
x= vt and y = (Vi * t)1/2* a * t^2
Yes! The second one is one of the constant acceleration equations. We know that our X and Y values are independent of each other, which is why Y doesn't matter here. We only care about the X position value since X and Y are independent! (This is an extremely important rule, trust me)
Therefore, we don't need to calculate a Y velocity or anything like that. We only need Y because we need to find time t. We can use Y to calculate time because although X and Y are independent of each other, they do share the same time traveled!
We know that [tex]V_{0,y}[/tex] = 0, since the car wasn't moving vertically initially. We also know Y initial is 100 and Y final is 0 when it hits the ground! The last thing we know is that the acceleration of any item in free fall is (usually) -9.81. Therefore, using the original Y equation that your teacher gave, we can plug things in and solve for time!
[tex]y_f=y_i+v_it+\frac{1}{2}at^2\\0=100+(0)t+\frac{1}{2}(-9.81)t^2\\-100=-4.905t^2\\t^2=20.39\\t=4.52[/tex]t = 4.52s
(Your teacher simplified the Y equation a little, so it may look slightly different from mine. I started at the original Y equation)
Now we have time! So now we can use the other equation your teacher provided. Again, remember, even though the car is now traveling through the air vertically, that does not affect its x velocity! The car is still traveling at 50m/s!
Therefore, we can just plug and chug!:
x = vt
x = (50)(4.52)
x = 226m
I hope this helps!
To understand the nature of electric fields and how to draw field lines In (Figure 2), what is wrong with panel B7 (Pick only those statements that apply to panel B) Electric field lines are a tool used to visualize electric foiled
Part B
In (Figure 2), what is wrong with panel B? (Fick only those statements that apply to panel B) Check all that apply.
Field liner caneot cross each other
The fold lines should be paraller becauze of the sheers symunner.
The field lnes chould spread apart as they leare the sheet to indiate mhr woakering of the field with gistance.
The field lines should always end on negative charges of at infinity.
in panel B, the field lines do end on negative charges, so this is not a problem No credit lost Try again D Submit Previous Answers
In (Figure 2), the wrong with panel B is: Field line can not cross each other the field lines should be parallel because of the sheers summoner.
What is electric field line?In general, an electric field line is a curve drawn with each point's tangent pointing in the direction of that point's net field. To designate the direction of the electric field from the two potential directions provided by a tangent to the curve, an arrow on the curve is obviously required. A field line is a space curve, or a three-dimensional curve.
The wrong with panel B is: Field line can not cross each other.
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The largest flowers in the world are the Rafflesia Arnoldii, found in Malaysia. A single flower is almost a meter across and has a mass up to 11.0 kg. Suppose you cut off a single flower and drag it along the flat ground. If the coefficient of kinetic friction between the flower and the ground is 0.39, what is the magnitude of the frictional force that must be overcome?
The magnitude of the frictional force that must be overcome is 42.04 N.
What is the magnitude of the frictional force?
The magnitude of the frictional force that must be overcome is calculated by applying Newton's second law of motion as follows;
Mathematically, the formula for the frictional force is given as;
F = μmg
where;
μ is the coefficient of frictionm is the mass of the flowerg is acceleration due to gravityThe magnitude of the frictional force that must be overcome is calculated as;
F = 0.39 x 11 kg x 9.8 m/s²
F = 42.04 N
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An airplane flies from Milwaukee to Chicago, a distance of 130 kilometers, and is in the air for 20 minutes. What is its average velocity? Show your work or explain how you got your answer.
The average velocity of the airplane between Milwaukee and Chicago is 1083.33 meter/second.
What is velocity?The rate at which a body's displacement changes in relation to time is known as its velocity. Velocity is a vector quantity with both magnitude and direction. SI unit of velocity is meter/second.
The total distance between Milwaukee and Chicago = 130 kilometer
= 1,300,000 meter.
Time interval = 20 minute = 20×60 second = 1200 second.
The average velocity of the airplane = total distance/time interval
= 1,300,000 meter / 1,200 second.
= 1083.33 meter/second.
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how is the energy of boiling water in an electric kettle a different energy from electric fan changing to kinetic energy
The energy of boiling water in an electric kettle is thermal energy, which is created by a transfer of electrical energy from the kettle to the water.
What is Energy?
Energy is a fundamental physical quantity that is a property of objects and their environment. It is the ability to do work and is often associated with the motion of objects. In physics, energy is defined as the capacity to do work and is measured in joules. It can take many forms such as thermal, kinetic, electrical, mechanical, and chemical.
Electric fan changing to kinetic energy is the conversion of electrical energy from the fan motor into kinetic energy, which is the energy of motion.
Kinetic energy is basically the energy of motion. It is the energy an object has due to its motion. It is defined as the work which is needed to accelerate a body of a given mass from rest to its current velocity.
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While skiing in Jackson, Wyoming, your friend Ben (of mass 63.2 kg) started his de- scent down the bunny run. 11.5 m above the bottom of the run. If he started at rest and converted all of his gravitational potential energy into kinetic energy, what is Ben's kinetic energy at the bottom of the bunny run? Use g = 9.8 m/s Answer in units of J.
Answer:
Approximately [tex]7.1 \times 10^{3}\; {\rm J}[/tex] (given: [tex]g = 9.8\; {\rm m\cdot s^{-2}}[/tex].)
Explanation:
To find the change in the gravitational potential energy ([tex]\text{GPE}[/tex]), use the formula:
[tex]\begin{aligned}& (\text{change in GPE}) \\ &= (\text{mass})\, (g)\, (\text{change in height})\end{aligned}[/tex].
Assume that gravitational field strength [tex]g[/tex] is constant (e.g., [tex]g = 9.8\; {\rm m\cdot s^{-2}}[/tex].) For an object of mass [tex]m[/tex], if the altitude of the object changes by [tex]\Delta h[/tex], the [tex]\text{GPE}[/tex] of that object would change by [tex]m\, g\, \Delta h[/tex].
In this question, the mass of Ben is [tex]m = 63.2\; {\rm kg}[/tex]. It is given that [tex]g = 9.8\; {\rm m\cdot s^{-2}} = 9.8\; {\rm N\cdot kg^{-1}}[/tex] and is constant. Since change in the altitude of Ben is [tex]\Delta h = 11.5\; {\rm m}[/tex], the change in the ([tex]\text{GPE}[/tex]) of Ben would be:
[tex]\begin{aligned} m\, g\, \Delta h &= (63.2\; {\rm kg}) \, (9.8\; {\rm N\cdot kg^{-1}})\, (11.5\; {\rm m}) \\ &\approx 7.1\times 10^{3}\; {\rm N\cdot m} = 7.1\times 10^{3}\; {\rm J} \end{aligned}[/tex].
The uniform beam has a weight W and length L and is supported by a pin at A and cable BC ( figure 1)
Part A
Determine the horizontal and vertical components of reaction at A
Express your answers in terms of some or all of the variables W, R. Φ and θ). Enter your answers separated by a comma.
View Available Hint's)
Aa + Ay = ____
Parts B
Determine the one cable car necessary to hold the beans position shown
Express your answers in terms of some or all of the variables W, R. Φ and θ).
The reaction is in A in vertical direction is W(2cosϕsinθ−sinϕcosθ)/2sin(θ−ϕ).
What is Normal Stress and Strain?In terms of psychology, "stress" and "strain" are sometimes used interchangeably in popular culture, as in the expressions "I'm feeling stressed" or "I'm under a lot of pressure."
In engineering, these phrases have specific, technical meanings. If a hook in the steel wire is attached,
If you hang the wire from the ceiling while placing a weight on the lower end, it will sag. By dividing the length change by the starting length, the strain in the wire may be computed.
Thus, as per the given scenario, W(2cosϕsinθ−sinϕcosθ)/2sin(θ−ϕ) will be the equation.
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On what basis is it considered that the universe is expanding?
There is strong evidence to support the idea that the universe is expanding. One of the main pieces of evidence for this is the observation of the cosmic microwave background radiation, which is a faint glow of microwave radiation that permeates the entire universe. This radiation is thought to be a residual heat left over from the Big Bang, the event that is believed to have marked the beginning of the universe.
The cosmic microwave background radiation has a very even temperature throughout the universe, but if the universe were not expanding, we would expect to see some regions that are slightly hotter or cooler than others due to differences in density. However, measurements of the cosmic microwave background radiation show that it has a very uniform temperature, which suggests that the universe must be expanding in order to even out any temperature differences that may have existed in the past.
Other evidence for the expansion of the universe includes the observation of supernovae in distant galaxies, which are explosions of massive stars that can be used to measure the distances to those galaxies. These measurements have shown that the most distant galaxies are moving away from us at a speed that is proportional to their distance, which is consistent with the expansion of the universe.
Hope This Helps You!
A 9.5 kg test rocket is fired vertically from Cape Canaveral. Its fuel gives it a kinetic energy of 2390 J by the time the rocket motor burns all of the fuel. The acceleration of gravity is 9.8 m/s². What additional height will the rocket rise? Answer in units of m.
Answer:
4.95 m
Explanation:
The rocket's initial kinetic energy is equal to the final gravitational potential energy, so we can set these equal to each other and solve for the additional height the rocket will rise:
KEinitial = KEfinal
1/2 * m * v^2 = m * g * h
Substituting the given values, we have:
1/2 * 9.5 kg * v^2 = 9.5 kg * 9.8 m/s^2 * h
Solving for h, we find that the additional height the rocket will rise is h = 2390 J / (9.5 kg * 9.8 m/s^2) = 4.95 m.
A 6 kg bowling ball is lifted 1.2 m into a storage rack. The acceleration of gravity is 9.8 m/s² Calculate the increase in the ball's potential energy. Answer in units of J.
Answer:
70.56 J
Explanation:
Gravitational Potential Energy= mass×gravitational pull× height
= 6×9.8×1.2= 70.56 J
with what speed will a clock have to be moving in order to run at a rest that is one half the rate of clock at rest
The speed at which a clock would have to be moving in order to run at half the rate of a clock at rest depends on the theory of relativity that you are using.
What is the clock speed about?In special relativity, time dilation is the phenomenon where time appears to pass differently for objects in motion relative to an observer at rest.
According to the theory, time appears to slow down for an object as it approaches the speed of light. The rate at which time appears to pass for an object is given by the equation:
T' = T / [tex]\sqrt{(1 - (v^2 / c^2))}[/tex]
Where T is the time as measured by an observer at rest, T' is the time as measured by an observer moving relative to the object, v is the velocity of the object, and c is the speed of light.
In addition, this is a theoretical scenario, practically in order to measure time dilation in a laboratory, it is required a very high precision of measurements, that are currently not possible.
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Most space lawyers agree that the barrier between airspace and outer space lies somewhere between where
the highest planes fly and the lowest satellites orbit.
True
False
True. The majority of space lawyers concur that the line dividing airspace from outer space is located halfway between the altitude at which airplanes fly and the orbital altitude of satellites.
What purposes do satellites serve?They serve a variety of functions, including that of the Satellite Navigation System, amateur radio, television transmission, and weather forecasting. In order to conduct study and acquire data, they also employ telescopes to view outward somewhere at solar system.
Do satellites provide internet access?Over 99% of Americans have access to satellite internet, along with most other (but certainly not all) rural residents. You do not need to have a home internet connection because the broadband signal is transmitted from satellites.
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I would like to ask for help in understanding on what basis the universe is considered to be expanding? As far as I understand, it is only an idea (hypothesis, theory) and not a scientific fact as the media presents it. Given that we on Earth receive evidence of various radiations from the past, we cannot say with certainty that the Universe is still expanding. Let's say the Universe stopped expanding 4 billion years ago and started contracting, would the results of all our observations be the same as they are or not?
Expansion of universe is not a hypothetical one but the universe is expanding in the sense increase distance over the space and dark matter.
What is universal expansion?The increase in distance over time between any two particular gravitationally unbound regions of the observable universe is known as the universe's expansion.
As a result, the size of space itself expands intrinsically. It is not necessary for space to exist outside of the cosmos or for it to extend into anything.
The metric changes in scale rather than space or the things in space moving in the conventional sense. Objects move farther apart from one another at ever-increasing speeds as the spatial component of the universe's spacetime metric scales up.
Any viewer in the cosmos would see that all of space appears to be expanding, except for the galaxies receding with a speed proportional to the distance from the observer.
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As shown in the picture above, an ice skater is skating at a constant speed in a circle. Is she accelerating? Explain your answer and draw the direction of the velocity in point A, B, C, and D.
Yes, the skater is accelerating.
Acceleration is a change in speed OR direction OR both. Since she's skating in a circle, her direction is constantly changing, so she is accelerating.
At A, her velocity points down.
At B, her velocity points right.
At C, her velocity points up.
At D, her velocity points left.
The anterior cruciate ligament in a woman's knee is 2.5 cm long and has a cross- sectional area of 0.54 cm2. If a force of 3000 N is applied longitudinally, how much will the ligament stretch? assume that young's modulus (1.8x10¹0 N/m²)
If a longitudinal force exceeding 3000 N is applied. Young's modulus for that object equals DL = 0.0139m.
Which is better, a greater or lower Young's modulus?The greater the modulus, or the lesser elasticity strain that arises from the application of a given stress, the stronger that medium is. Young's modulus, sometimes referred to as mechanical performance, is a metric used to determine how stiff a material is. In other words, it is readily bent or stretched.
Young's modulus really measures a material's ability to withstand changes in length when compressed or under stress along its length. Divide the primary stresses by the strain to get Young's modulus, commonly known also as young's modulus.
Young's modulus Y= stress/strain
= (F/A) /(DL/L)
F=3000N,
A=0.54 cm²,
L=2.5cm,
Y=0.1 Gpa
0.1 * 10⁹ = (3000/(0.54* 10⁻⁴) (2.5 ⋆ 0.01/DL)
DL = 0.0139m
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1- A ball, M = 4 kg is released from rest (vi =0) at a height, h = 2 m above the ground. (a)
What is the kinetic energy of the ball just before it hits the ground? What is the change in the
potential energy, ΔU during this motion? (b) Find the kinetic energy of the ball at a height, y
= 1.2 m above the ground. (Take g = 10 m/s2
).
(a) The kinetic energy of the ball just before it hits the ground is 78.4 J.
(b) The kinetic energy of the ball at a height of 1.2 m is 31.36 J.
What is the kinetic energy of the ball?The kinetic energy of the ball just before it hits the ground is calculated as follows;
K.E ( bottom) = P.E (top)
P.E (top) = mgh
where;
m is the mass of the objecth is the height of the objectg is acceleration due to gravityP.E (top) = 4 x 9.8 x 2
P.E (top) = 78.4 J
The change in the potential energy of the ball during its motion is calculated as follows;
ΔU = P.Ef - P.E i
where;
P.Ef is the final potential energy at ground levelP.Ei is the initial potential energy at maximum heightΔU = 0 J - 78.4 J
ΔU = -78.4 J
The kinetic energy of the ball at a height of 1.2 m is the change in the potential energy of the ball and it is calculated as follows;
K.E = -ΔU
K.E = -mg (hf - hi)
K.E = (4 x 9.8)(2m - 1.2 m)
K.E = 31.36 J
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