Question #8e9bb

1 Answer
Feb 12, 2018

#15kN# opposite to the direction of travel.

Explanation:

#F=ma#, we know that much.

We also know that in order to stop the car it has to decelerate from #30ms^-1# to #0ms^-1# in 3 seconds.

We can figure out that deceleration by

#a = (Deltav)/(Deltat) = (30ms^-1-0ms^-1)/(3s) = 10ms^-2#

Therefore, the force applied to the car must be

#F = 1500kg xx 10ms^-2 = 15,000N = 15kN#