Question

An SUV is traveling at a speed of 18 m/s. If the SUV has a mass of 1,550 kg, what force must be applied to stop it in 8 seconds?

A. –4,030.7 N
B. –2,700.0 N
C. –3,487.5 N
D. –2.25 N

Answer 1

Given

u=18m/s

v=0m/s

t=8seconds

m=1550 kg

Solution

a=(v-u)/t

a=(0-18)/8

a=(-18)/8

a=(-9)/4 m/s2

or

a=-2.25 m/s2

From Newton's second law motion

F=ma

F=1550×(-2.25)

F=-3487.5N