Question

A train whose weight is 16 metric tons, moves at the rate of 72 kmph. after applying brakes it stops in 500 meters. what is the force executed by brakes?

Answer 1

m=16000kg
u=20m/s
v=0m/s
s=500m
according to third equation of motion
${v}^{2} - {u}^{2} = 2as$
0^2 - 20^2 =2×a×500
=>-400=1000a
a=-400/1000=-0.4m/s^-2

F=M×A=16000×0.4=6400N