Question

A person throws a pen to their friend across the room. Draw the free body diagram for the pen as it is in flight. Ignore air resistance.

Answer 1

When the person throws a pen to his friend across the room, he has to throw with some initial velocity at some angle to horizontal.

As there is no air resistance, the only force that acts all time on the body during it's flight is only gravitational force or force by gravity.

due to this force the body is accelerated only downward, and there is no acceleration in horizontal direction.

during its flight, when it reaches it's highest point, there is only horizontal component of velocity.

the path followed by the pen will parabolic.