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

AI Thread Summary
Car A travels a distance of 517 m at a constant velocity of 24.6 m/s over 21 seconds. Car B starts from rest and accelerates to cover the same distance in the same time. The formula for displacement under constant acceleration, s = (u + v)/2 * t, is applied to determine the final velocity and acceleration of Car B. Using the initial velocity of zero for Car B, the final velocity can be calculated, and the acceleration is found by dividing the final velocity by the time of 21 seconds. The discussion clarifies the calculations necessary to find the required values for both cars.
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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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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.
 
@ 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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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.
 
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