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A car starts from rest and speeds up at a constant rate of 2.03 m/s^2 in a straight line until it reaches a speed of 21.1 m/s. The car then slows down at half the rate that it sped up until it stops. How far (in m) does the car move from start to stop?

Respuesta :

gilcarusolautaro

Answer:

The car moves from start to stop 328.88 m in total.

Explanation:

Vo= 0 m/s

V1= 21.1 m/s

V2= 0 m/s

a1= 2,03 m/s²

a2= -1.015 m/s²

Speed Up:

Speed up time:

V1= Vo + a1 * t1

t1= V1/a1

t1= 10.39 sec

total distance of speed up:

d1= Vo * t1 + (a1 * t1²)/2

d1= 109.57m

Slow Down:

V2= V1 - a2 * t2

t2= V1/a2

t2= 20.78 sec

total distance of slow down:

d2= V1 * t2 - (a2 * t2²)/2

d1= 219.31m

Total Distance:

TD= d1+d2= 109.57m + 219.31m

TD= 328.88 m