Question

Which of the following forces can change velocity?

Acceleration forces
Equal and opposite horizontal forces
Equal and opposite vertical forces
Unequal, opposite forces

Answer 1

Unequal opposite forces.
(They're unbalanced.)

Answer 2

Option A and Option D are correct.

Step-by-step explanation:

We have the Newton's second law, that is rate of change of momentum is force.

`(dP)/(dt)=F\\\\(mv-mu)/(dt)=F`

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.