A Smart Car, which has a mass of 1000 kg, is going 20 m/s. When it hits the barrier, it stops at a time of 0.5 seconds. What is the force on the car?

The force = F =  -40000 N

Explanation:

We know that,

Calculating the acceleration

using the formula

a = (v₂ - v₁) / t

   = 0 - 20 / 0.5

  = -20 / 0.5

   = -40 ms⁻²

Thus, acceleration (deceleration) = a = -40 ms⁻²    

Note: negative sign gives us an idea the car is slowing down after a collision with the barrier, thus acceleration and velocity are in opposite direction.

We know that

F = ma

   = 1000 × -40

   = -40000 N

Thus, the force = F = -40000 N

acceleration = (change in speed) / (time for the change)

change in speed = (20-120)= -100 m/s.

1.5 min = 90 sec

acceleration = -100/90 = -1.11 m/s^2.

we don't care about the 150kg or the 2,500 meters. they don't make any difference.

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