A person is pushing a block on a rough surface with a force that is larger than

Question

A person is pushing a block on a rough surface with a force that is larger than the kinetic friction of the block so that the block accelerates. As the block accelerates:

A. The force that the person exerts on the block = the force that the block exerts on the person + the force of kinetic friction between the block and the surface
B. The force that the person exerts on the block must be larger than the force that the block exerts on the person so that the block can move.
C. The acceleration of the block is equal to k g, where k is the coefficient of kinetic friction and g is gravitational acceleration.  

Wouldnt it be A? because the amount of force the person exerts on the block would be equal to the force the block exerts on the person?

Explanation / Answer

Yes.

The amount of force the person exerts on the block would be equal to the force the block exerts on the person.

Then a question arises that if both the forces are equal and opposite, then why does the block move at all.

The reason is that the block is also exerting a force on the ground, which is external to the block-person, and the ground exerts a force back on the block-person system causing it to accelerate.

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