Question

An object of mass 5kg moving with an initial velocity of 30m/s ti make it to come to rest in 6 secs what is the force required ? What is the direction of the force

Answer 1

m =5kg
u= 30m/s
v=0
t=6sec

f=ma
=m(v-u) /t
=5(0-30)/6
5(-30)/6
=-25N

the direction of the force is opposite

Answer 2

m=5kg
u=30m/s
v=0m/s
t=6s
a=v-u/t using first equation of motion
(0-30)/6= -5m/s2
f=m*a
5*-5 =25N
direction is opposite to direction of applied force