Finding constant velocity,final velocity and acceleration of these cars?

In summary, two cars cover a distance of 517 m in 21 seconds while moving in the + direction. Car A travels at a constant velocity of 2.40 m/s, while Car B starts from rest and reaches a final velocity of 24.6 m/s in 21 seconds, with a constant acceleration of 1.17 m/s^2.
  • #1
xod_s
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Homework Statement


Two cars go the same distance in a straight line. Car A covers the distance at a constant velocity. Car B starts from rest and maintains a constant acceleration. Both cars cover a distance of 517 m in 215 and are moving in the + direction. Whats the constant velocity of car A as well as the final velocity and acceleration of car B?

Homework Equations





The Attempt at a Solution

 
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  • #2
xod_s said:

Homework Statement


Two cars go the same distance in a straight line. Car A covers the distance at a constant velocity. Car B starts from rest and maintains a constant acceleration. Both cars cover a distance of 517 m in 215 and are moving in the + direction. Whats the constant velocity of car A as well as the final velocity and acceleration of car B?

Homework Equations





The Attempt at a Solution


Did you by any chance mean 21 s [seconds] rather than 215 and no units.
 
  • #3
@ PeterO "Did you by any chance mean 21 s [seconds] rather than 215 and no units."
Yes I did.Thank you for pointing that out.It's supoose to be 21 seconds not vaugely 215.Also if it helps I know for sure that the constant velocity of Car A is 2.40 m/s.
 
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  • #4
xod_s said:
@ PeterO "Did you by any chance mean 21 s [seconds] rather than 215 and no units."
Yes I did.Thank you for pointing that out.It's supoose to be 21 seconds not vaugely 215.Also if it helps I know for sure that the constant velocity of Car A is 2.40 m/s.

I hope you really meant 24.6 for the constant velocity.

One of the useful formulae for motion under constant acceleration is

s = (u + v)/2 .t

s = displacement, u = initial velocity, v = final velocity, t = time.

for acceleration zero, u = v so the (u + v)/2 = (v + v)/2 = v

The formula becomes s = vt, which you use to get that 24.6

when an object starts from rest, u = zero, so the formula becomes s = v/2 . t

from that you can get the final velocity.

as for acceleration .. the car reaches that velocity in 21 seconds, so you can divide by 21 to find the acceleration.
 
  • #5


To find the constant velocity of car A, we can use the formula v = d/t, where v is velocity, d is distance, and t is time. We know that both cars cover a distance of 517 m in 215 seconds, so the constant velocity of car A would be 517/215 = 2.41 m/s.

To find the final velocity of car B, we can use the formula v = u + at, where v is final velocity, u is initial velocity (which is 0 in this case), a is acceleration, and t is time. We know that car B starts from rest and maintains a constant acceleration, so we can use the given distance and time to find the final velocity. Plugging in the values, we get v = 0 + a(215), which simplifies to v = 215a. To find the acceleration, we can use the formula a = (v-u)/t, where v is final velocity, u is initial velocity, and t is time. Since we know that the final velocity is 517 m/s and the initial velocity is 0, we can substitute these values to get a = (517-0)/215 = 2.41 m/s^2. Therefore, the final velocity of car B is 517 m/s and the acceleration is 2.41 m/s^2.

In conclusion, the constant velocity of car A is 2.41 m/s, the final velocity of car B is 517 m/s, and the acceleration of car B is 2.41 m/s^2. It is interesting to note that both cars have the same constant velocity and acceleration, even though car B started from rest and maintained a constant acceleration. This is because the two cars traveled the same distance in the same amount of time, so their average velocities and accelerations are equal.
 

FAQ: Finding constant velocity,final velocity and acceleration of these cars?

How do I calculate constant velocity?

Constant velocity is calculated by dividing the distance traveled by the time it takes to travel that distance. The formula for constant velocity is v=d/t, where v is velocity, d is distance, and t is time.

How do I find the final velocity of a moving object?

The final velocity of a moving object can be found by adding the initial velocity to the product of acceleration and time. The formula for final velocity is vf = vi + at, where vf is final velocity, vi is initial velocity, a is acceleration, and t is time.

What is acceleration and how is it calculated?

Acceleration is the rate at which an object's velocity changes over time. It is calculated by dividing the change in velocity by the time it takes for that change to occur. The formula for acceleration is a=Δv/Δt, where a is acceleration, Δv is change in velocity, and Δt is change in time.

Can a moving object have a constant velocity and changing acceleration?

Yes, a moving object can have a constant velocity and changing acceleration. This can happen when the object is moving at a constant speed in a circular motion, where the direction of the velocity is constantly changing. In this case, the magnitude of the velocity remains constant, but the direction changes, causing a changing acceleration.

How can I use the equations for constant velocity and acceleration to analyze the motion of a car?

To analyze the motion of a car, you can use the equations for constant velocity and acceleration to calculate its speed, final velocity, and acceleration at different points in time. By plotting these values on a graph, you can visualize the car's motion and determine if it is accelerating, decelerating, or maintaining a constant speed. This can also help in identifying any changes in the car's velocity and acceleration, which can be useful in determining its performance and efficiency.

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