Question

A man standing at the top of a tower has two spheres A and B. He drops sphere A downwards and throws sphere B horizontally at the same time. Which of the following is correct ?
I) Both the spheres will reach the ground simultaneously.
II) A will reach the ground first.
III) B will reach the ground first.

• A. I is correct
• B. II is correct
• C. III is correct
• D. None

Answer 1

The correct option is A I is correct

Statement A is correct
Since the time of flight is governed by vertical distance and velocity in vertical direction, In above case both are same for 2 spheres
hence both spheres should reach ground simultaneously
Case A: $s=\frac{1}{2}g{t}^2$
$\Rightarrow t_f=\sqrt{\frac{2s}{g}}$
For
Case B: $s=ut+\frac{1}{2}g{t}^2$

Given $u=0$
$t_f=\sqrt{\frac{2s}{g}}$