Answer:
Option A and Option D are correct.
Explanation:
We have the Newton's second law, that is rate of change of momentum is force.
[tex]\frac{dP}{dt}=F\\\\\frac{mv-mu}{dt}=F[/tex]
So if there is a force mv - mu ≠ 0
v - u ≠ 0
v ≠ u
Final velocity ≠ Initial velocity.
a) Option A is correct since there is a force
b) Option B is wrong since total force is zero.
c) Option C is wrong since total force is zero.
d) Option D is correct since there is an effective force
Option A and Option D are correct.