Question #020f1

1 Answer
Jan 8, 2017

Velocity of the car just brfore its impact with the stationary truck is #v_i=2"m/s"# The car comes to rest finally, So its final velocity #v_f=0"m/s"#.The car travels #5m# after its impact.Hence #s=5m#

Using equation of kinematics we can write

#v_f^2=v_i^2-2as#,where #a# is the average retardation produced.

#0^2=20^2-2axx5=>a=40"m/"s^2#

So the force exerted by the seat belt on the passenger of mass #m=90kg# will be

#F=ma=90xx40N=3600N#