A student throws a heavy red ball horizontally from a balcony of a tall building with an initial speed v0. At the same time, a second student drops a lighter blue ball from the same balcony. Neglecting air resistance, which statement is true?

(A) The blue ball reaches the ground first.
(B) The balls reach the ground at the same instant.
(C) The red ball reaches the ground first.
(D) Both balls hit the ground with the same speed. (E) None of the above statements is true.

(B) The balls reach the ground at the same instant.

Explanation:

Since it is a projectile motion, the time required to reach the ground is given by

t = √2h/g

Where h is the height from which the balls are thrown and g is the acceleration due to gravity.

Since both of the balls were thrown from the same height and the acceleration of both balls are also same they will reach the ground at the same instant.

the diagram which shows forces as either balanced = same speed or unbalanced = accelerarting