Question

What force must the brakes apply to a 2800 kg
truck going 30 meters per second to bring it to
rest in 8.0 seconds
(a) 12000 N
(b) 13000 N
(C) 10500 N
(d) 12500 N​

Answer 1

Explanation:

The answer is c which is 10500 N

Answer 2

Explanation:

given that : mass of truck=2800kg,

intial velocity(u)= 30m/s, final velocity(v)=0m/s, time taken by truck= 8s,

find acceleration

a= v-u/t = 0-30/8 = -15/4 m/s2

then force acting on it

F=ma= 2800(-15/4) =-10500N

Force = 10500N