Thread: Solve time and distance??

Hey There,
An electric car starts from rest and accelerates at a rate of 2.0 m/s^2 in a straight line until it reaches a speed of 20 m/s. The car then slows at a constant rate of 1.0 m/s until it stops.

a) how much time elapses from start to stop?
b) how far does the vehicle travel from start to stop?

So I have:
Vo= 0 m.s
a = 2.0 m.s.s
V = 20 m/s
a when it slows 1.0 m.s


IS THIS CORRECT, PLEASE CHECK FOR ME
Time for first half of run 10 s and 20 s for 2nd part. So total time start to stop is 30 s.

Distance first half is 100 m and 200 m for 2nd part. SO Total distance is 300m.

Do I have it correct??

I found time for start to the 20 m.s and then 20m.s to stop.
Same with time.
Added them both.
Let me know thanks.

Originally Posted by bradycat

Hey There,
An electric car starts from rest and accelerates at a rate of 2.0 m/s^2 in a straight line until it reaches a speed of 20 m/s. The car then slows at a constant rate of 1.0 m/s until it stops.

a) how much time elapses from start to stop?
b) how far does the vehicle travel from start to stop?

So I have:
Vo= 0 m.s
a = 2.0 m.s.s
V = 20 m/s
a when it slows 1.0 m.s


IS THIS CORRECT, PLEASE CHECK FOR ME
Time for first half of run 10 s and 20 s for 2nd part. So total time start to stop is 30 s.

Distance first half is 100 m and 200 m for 2nd part. SO Total distance is 300m.

Do I have it correct??

I found time for start to the 20 m.s and then 20m.s to stop.
Same with time.
Added them both.
Let me know thanks.

correct.

Thanks to let me know. Joanne