Question

compare the inertia of 2 balls A and B of masses m and 2m are in motion with velocity 2v and v

Answer 1

(i) (Mass of ball A) < (Mass of ball B)  Ball B has more inertia than A. (ii) Momentum of ball A = 2mv Momentum of ball B = 2mv. (iii) Since both the balls have same momentum, so there is need of same force to stop them because rate of change of momentum is force.

Answer 2

Given:
Two balls A and B of mass m and 2m
Initial velocity of first ball =2V
Initial velocity of second ball= V
1)Compare inertia:
As inertia is measure of mass. Hence the object with greater mass has more mass.
So, Ball B is having more inertia.
2)Compare momentum:
Momentum is the product of mad and velocity.
P= mxv
So Pa=mx2v=2mv
Pb=2mxv=2mv
So, momentum in both the cases are same.
3)The force needed to stop them in same time:
From Newton's second law:
F= dp/dt
= change in monentum/dt
= 0-2mv/time
As momentum is same for given time , so same force is required to stop them.