A vehicle can accelerate or decelerate at a maximum value of 1m/s^2 and can attain a maximum speed of 20m/s if it starts from rest what is the shorest time it can travel 1000m in a staright path if it comes tp rest at the end of 1000m

Question

anonymous · Answer

@ajprincess  we have to find t3 tooo but how???

amistre64 · Answer

t3 = t1 doesnt it?

anonymous · Answer

No

amistre64 · Answer

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anonymous · Answer

i think we have to find the distance  but sont knw hw??

amistre64 · Answer

a(t) = 1

v(t) = t

how long does it take to get from 0 to 20?

anonymous · Answer

20s

amistre64 · Answer

we can integrate v(t) from 0 to 20 to find its displacement

$$\int t\ dt=t^2/2$$

0 is trivial, so 20^2/2 = 200 meters to start with

anonymous · Answer

1st  it is travellling with acceleration next with constant speed and last with deceleration we have to find the distance

amistre64 · Answer

it slows down as fast as it speeds up, right?

amistre64 · Answer

so t1 = t3

anonymous · Answer

yes u r correct

anonymous · Answer

yes t1=t3   we have to find t2 at constant speed

amistre64 · Answer

400 meters is taken up by speeding up and slowing down

amistre64 · Answer

600 meters left to go 20 meters per sec

amistre64 · Answer

20t = 600 when t = 30 i believe