A train accelerates from 23m/s to 190m/s in 54 seconds. What was its acceleration?

Answer: B

Explanation:

The conservation of momentum states that the initial momentum of the system must equal the final momentum of the system. Our system in this case is the two colliding objects and ONLY the two colliding objects. Initially, our system had mass 1 moving towards a stationary mass 2. The stationary mass has a velocity of 0m/s and therefore has no momentum. The initial momentum would then be:

[tex]p_i=m_1v_1_i+m_2v_2_i[/tex]

[tex]p_i=m_1v_1_i[/tex]

The final momentum depends on what type of collision occurred. This case is the simplest type of collision, when the objects stick to each other and act as one. Since the objects move together, their velocity must be the exact same. Our final momentum looks like:

[tex]p_f=m_1v_f+m_2v_f[/tex]

[tex]p_f=v_f(m_1+m_2)[/tex]

Setting the initial momentum equal to the final momentum:

[tex]p_i=p_f[/tex]

[tex]m_1v_1_i=v_f(m_1+m_2)[/tex]

Solving the final velocity:

[tex]v_f=m_1v_1_i/(m_1+m_2)[/tex]

Which matches answer B

The two given graphs can be displaying the motion of the different objects. As the distance-versus-time graph shows the speed is constant while the speed-versus-time graph shows the uniform acceleration motion.

A uniformly accelerated motion is one in which the acceleration of the object throughout the motion is uniform. When an object is moving in a straight line with an increase in velocity at equal intervals of time, then we can say that object has uniform acceleration.

Projectile motion is an example of motion in a plane with uniform acceleration. The only acceleration acting on the particle is the acceleration due to gravity (g)  in the case of projectile motion. Since there is no acceleration in the horizontal direction, the velocity in the x-direction will be constant.

In the distance-versus-time graph, the straight line passing through the origin shows the increase in the distance at equal intervals of time. So, the speed of the object will be constant.

The speed-versus-time graph shows the increase in the speed at equal intervals of time. So, the acceleration of the object will be constant. So this is the graph of the motion of a different object.

Learn more about uniform acceleration motion, here:

https://brainly.com/question/28012775

#SPJ2

Answer: 6 N

Explanation: W (WORK) = 15 JOULES

                      S (DISTANCE) = 2.5 m

                       F (FORCE) = ?

              BY USING FORmULA OF WORK DONE

                     W = F.S

                      F =W/S

                      F = 15/2.5

                      F =  6 N

Explanation:

The current which flows through the circuit is dependent on the resistance of the material/device. Given by the equation U=RI

If U becomes 2U

And I becomes 3 I

then R×2=3

R=3/2=1.5 Ω

Hope this answers your question?

Answer:

Speed = Distance/ Time

Time= Distance/ Speed

=240/30= 8 hours

Explanation:

Hope this helps u

Crown me as brainliest:)

For a wheel  composed of a 10-kg hoop stiffened by four thin spokes and each with a mass of 2 kg, the angular velocity  is mathematically given as

w=1.165 rad/s

Generally, the equation for the  angular velocity  is mathematically given as

[tex]V = \sqrt{(F * r/m)[/tex]

Therefore

[tex]V= \sqrt{(40 x 0.3 / 98.1)[/tex]

V= 0.35 m/s

Where

w=v/r

w= 0.35/0.3

w=1.165 rad/s

In conclusion, the angular velocity is

w=1.165 rad/s

Read more about Speed

https://brainly.com/question/4931057

Answer:

Explanation:

In order to find the distance covered we use the formula

From the question

velocity = 0.24 m/s

time = 5 s

We have

distance = 0.24 × 5

We have the final answer as

Hope this helps you

Answer:

-5 m/s^2

Explanation:

[tex]acceleration = \frac{change \: in \: velocity}{time} \\ \\ = \frac{15 - 25}{2} \\ \\ = \frac{ - 10}{2} \\ \\ = - 5 \: m {s}^{ - 2} \\ \\ negative \: sign \: represents \: that \: \\ object \: is \: slowing \: down.[/tex]

Explanation:

Acceleration is the change in velocity over time.

a = Δv / Δt

a = (15 m/s − 25 m/s) / 2.0 s

a = -5.0 m/s²

The magnitude of the acceleration is 5.0 m/s².

Answer:

Mass of substance m = 0.050Kg

Initial Temperature T₁ = 20°C

Final Temperature T₂ = 100°C

we have to calculate the heat absórbed by the lead .

Since spècific heat of lead is not gíven so we will take spècific heat of lead 128 J/kg°C

[tex] \diamond \bf \: Q\: = m \times c( \Delta \: t) [/tex]Put the given value

[tex]\sf \longrightarrow \: Q = 0.050 \times 128 \times (100 - 20) \\ \\ \\ \sf \longrightarrow \: Q = 0.050 \times 128 \times (80) \\ \\ \\ \sf \longrightarrow \: Q = 6.4 \times 80 \\ \\ \\ \sf \longrightarrow \: Q = 512 \: joules[/tex]

Therefore,

Explanation:

Weight = Fg = mg = (60 kg)*(9.8 m/s2) = 588 N.

Answer:

The best estimate of the depth of the well is 2.3 sec.

Explanation:

Given that,

Record time,

[tex]t_{1}=2.19\ sec[/tex]

[tex]t_{2}=2.30\ sec[/tex]

[tex]t_{3}=2.26\ sec[/tex]

[tex]t_{4}=2.29\ sec[/tex]

[tex]t_{5}=2.27\ sec[/tex]

We need to find the best estimate of the depth of the well

According to record time,

We can write of the record time

[tex]t_{1}=2.19\approx 2.2\ sec[/tex]

[tex]t_{2}=2.30\approx 2.3\ sec[/tex]

[tex]t_{3}=2.26\approx 2.3\ sec[/tex]

[tex]t_{4}=2.29\approx 2.3\ sec[/tex]

[tex]t_{5}=2.27\approx 2.3\ sec[/tex]

Here, all time is nearest 2.3 sec.

So, we can say that the best estimate of the depth of the well is 2.3 sec.

Hence, The best estimate of the depth of the well is 2.3 sec.

Answer:

Drawing Bohr Models

1. Draw the nucleus.

2. Write the number of Protons and  Neutrons in the nucleus

3. Draw the first shell

4. Add the electrons, the first shell  can only hold 2

5. Draw the next shell if you  have more electrons to add

6. Add your electrons, the 2nd  shell can hold up to 8

7. Check yours Valence  electrons

Explanation:

Answer:

a= 9.81 s

Explanation:

vi= 8m/s

a= -9.81 m/s

d= 640m

t= 40s

1. Find final velocity

vf= vi +a(t)

vf= 8m/s + -9.81m/s x 40s

vf = -384.4 m/s

acceleration= change in velocity/ change in time

a= -384.4- 8= -392.4/ 40s = 9.81s

a= 9.81 m/s

Hopefully this helps and is correct! Much love ❤️

Answer:

Foam

Explanation:

Took the test

The materials that are typically used as a thermal insulator are foam and ceramic.

The object that blocks the heat from transferring from one area to another is referred to as a thermal insulator.

Here,

The reduction of heat transfer (the movement of thermal energy between objects of different temperatures) between objects in thermal contact or within the impact of radiation is known as thermal insulation. In addition to using the right object forms and materials, specially engineered technologies or processes can also be used to provide thermal insulation.

The broad term for thermal preserving and heat insulating materials is thermal insulating materials, often known as materials or material complexes that appear to be resistant to thermal currents. Heat insulation prevents heat from leaving whereas thermal preservation stops heat from escaping or spreading.

Hence,

The materials that are typically used as a thermal insulator are foam and ceramic.

To learn more about thermal insulator, click:

https://brainly.com/question/23134662

#SPJ5

If the sphere is positively charged, the positive rod is repelled by the sphere while the negative rod is attracted by the sphere.

An electrical charge can be positive or negative. From the laws of electrostatics, unlike charges attract while like charges repel. As such the effect observed when the rods are individually brought near the sphere will decide the charge on the sphere.

If the sphere is neutral, there is no effect observed when each rod is brought near the sphere. If the sphere is positively charged, the positive rod is repelled by the sphere while the negative rod is attracted by the sphere.

Learn more about electrostatics: https://brainly.com/question/9774180

Answer: A reference frame is simply a perspective, context, or point of view. In physics that typically means physical space time coordinates, in the social sciences it takes on a slightly different meaning. In both fields, everything is relative to the point of view of the observer ( relativity ).

Explanation:

Answer:

In physics, a frame of reference consists of an abstract coordinate system and the set of physical reference points that uniquely fix the coordinate system and standardize measurements within that frame. For n dimensions, n + 1 reference points are sufficient to fully define a reference frame.

Explanation:

Also called reference frame. Physics. a framework that is used for the observation and mathematical description of physical phenomena and the formulation of physical laws, usually consisting of an observer, a coordinate system, and a clock or clocks assigning times at positions with respect to the coordinate system.

Reference frame, also called frame of reference, in dynamics, system of graduated lines symbolically attached to a body that serve to describe the position of points relative to the body.

Choosing a frame of reference requires deciding where the object's initial position is and which direction will be considered positive. ... Frames of reference are particularly important when describing an object's displacement. Displacement is the change in position of an object relative to its reference frame.

Actually, frames of references are classified into two types depending upon how they are moving. Those two types are called inertial and non-inertial frames of reference. An inertial frame of reference has no acceleration. The law of inertial holds in such a frame; no fictitious forces arise.

Answer:

True

Explanation:

i did the Quiz

Answer:

A: true

Explanation:

I took the test its right, trust me I got 100%

Answer:

It would move forward.

Explanation:

The frequency of the sound heard by the driver of car B from car A is mathematically given as

F=738.6hz

Question Parameters:

A car moves at 72 km/h and car B moves at 90 km/h, approaching each other. A car honked with a frequency of 650 Hz

the speed of the sound waves in the air is 350 m/s,

Generally, the equation for the Frequency   is mathematically given as

[tex]F=f'(\frac{v+vob}{v-vsource})[/tex]

Therefore

[tex]F=650(\frac{350+25}{350-20})[/tex]

F=738.6hz

In conclusion, the frequency of the sound is

F=738.6hz

Read more about Distance

https://brainly.com/question/4931057

Answer:

When 1 Joule of work is done to move a charge of amount 1 Coulomb from one place to another, then it is said that the potential difference between the two points is 1 Volt (V)

Answer:

The velocity of the frozen rock at [tex]t = 1.5\,s[/tex] is -14.711 meters per second.

Explanation:

The frozen rock experiments a free fall, which is a type of uniform accelerated motion due to gravity and air viscosity and earth's rotation effect are neglected. In this case, we need to find the final velocity ([tex]v[/tex]), measured in meters per second, of the frozen rock at given instant and whose kinematic formula is:

[tex]v = v_{o} + g\cdot t[/tex] (Eq. 1)

Where:

[tex]v_{o}[/tex] - Initial velocity, measured in meters per second.

[tex]g[/tex] - Gravity acceleration, measured in meters per square second.

[tex]t[/tex] - Time, measured in seconds.

If we get that [tex]v_{o} = 0\,\frac{m}{s}[/tex], [tex]g = -9.807\,\frac{m}{s^{2}}[/tex] and [tex]1.5\,s[/tex], then final velocity is:

[tex]v = 0\,\frac{m}{s}+\left(-9.807\,\frac{m}{s^{2}} \right) \cdot (1.5\,s)[/tex]

[tex]v = -14.711\,\frac{m}{s}[/tex]

The velocity of the frozen rock at [tex]t = 1.5\,s[/tex] is -14.711 meters per second.

[tex]\Large \boxed{\displaystyle density \ (kgm^{-3})=\frac{mass\ (kg)}{volume \ (m^3)} }[/tex]

Answer: D. Cobalt

Explanation: Cobalt has excellent magnetic properties so it is D. Cobalt.

The element which has magnetic properties from the given list of elements would be cobalt , therefore the correct answer is option C.

The elements of the periodic tables that behave as metals, as well as the nonmetal in some chemical or physical aspects, are known as metalloids. Some examples of metalloids are Boron , silicon , germanium, arsenic , antimony , tellurium , etc.

As given in the problem we have to find out the element which possesses the magnetic properties from the given list ,

Calcium belongs to group 2 of the periodic table and nonmagnetic element . Similarly , carbon is a nonmagnetic material .

Thus , the element which has magnetic properties from the given list of elements would be cobalt, therefore the correct answer is option C .

Learn more about metalloids from here, refer to  the link given below ;

brainly.com/question/2548493

#SPJ6

Answer:

it will sink because object that have less they float not more

Answer:

it will sink here's why

Explanation: The density of an object determines whether it will float or sink in another substance. An object will float if it is less dense than the liquid it is placed in. An object will sink if it is more dense than the liquid it is placed in.

third

Explanation:

i think so because finding structure of dna can help a lot for well being of human being

Answer:

x = 333.33 [m]

Explanation:

To solve this problem we must use the following kinematics equation.

[tex]v_{f}^{2} = v_{i}^{2}-(2*a*x)[/tex]

where:

Vf = final velocity = 0

Vi = initial velocity = 20 [m/s]

a = desacceleration = 0.6 [m/s^2]

x = distance [m]

Note: the final speed is zero as the body finishes its movement.

Now replacing:

0 = (20)^2 - (2*0.6*x)

1.2*x = 400

x = 333.33 [m]

The final velocity of the Jet from the takeoff is 15.5 m/s.

The final velocity of the jet is determine by applying second kinematic equation, using the principle of average velocity as shown below.

s = (u + v)t/2

where;

s = (0 + v)t/2

2s = vt

v = 2s/t

v = (2 x 9.3) /1.2

v = 15.5 m/s

Thus, the final velocity of the Jet from the takeoff is 15.5 m/s.

Learn more about final velocity here: https://brainly.com/question/25905661