Question

In a football match a goal attempt by messi is stopped by neuer in 0.2 sec. If mass of the ball is 400g and the force applied by neuer was 120N what was the speed by which messi hit the ball?

Answer 1

Force=mass×acceleration

Mass=400g

=0.4kg

120=0.4×a

a=120÷0.4

a=300m/s^2

V(final velocity)=0

Time=0.2sec

Acceleration =300m/s2

v=u+at

0=u+300×0.2

0=u+60

u=60 m/s

Therefore speed =60m/s