2. A particle of mass m and speed v collides at right angles with a very massive wall in a perfectly elastic collision. The magnitude of the change of momentum of the particle is
a.) zero
b.) mv/2
c.) mv
d.) �ã (2) mv
e.) 2mv
Hint: the final momentum is equal in magnitude and opposite in direction. Calculate the change.
If you have no idea what the answer is, you'd be better off reading about momentum than posting questions here.