Question

3.answer this question

Answer 1

Hi!
a) Momentum is the motion contained in a body.
It's SI unit is kg m/s.

b) mass m=10 kg
For a freely falling body,u=0
h=5 m
g=10 m/s*s
From equation of motion, v*v=(u*u)+2gh
                                         v*v=0+2*10*5
                                         v*v=100
                                         v=10
Momentum of body=mv
                                 10*10
                                  100 kg m/s

c)We get hurt when we hit a wall bcoz as we apply a force on the wall,by newton's third law,the wall also applies equal force on our hand. So.we get hurt.

d) From F=ma,
              a=F/m
Now,F'=2F
        m'=2m
        a'=F'/m'
        a'=2F/2m
        a'=F/m
Thus, acceleration remains constant.