Question

A ball is thrown from height $h$ and another from $2h$ The ratio of time taken by the two balls to reach ground is:

• A. $1:\sqrt{2}$
• B. $\sqrt{2}:1$
• C. $2 : 1$
• D. $1 : 2$

Answer 1

Answer: (A)

$1:\sqrt{2}$

Answer 2

For first ball, $h=0 \times t_{1}+\frac{1}{2} g t_{1}^{2}$ $\Rightarrow t_{1} =\sqrt{\frac{2 h}{g}} \ldots$(i) For second ball, $2 h=0 \times t_{2}-\frac{1}{2} g t_{2}^{2}$ $\Rightarrow t_{2}=\sqrt{\frac{4 h}{g}} \ldots$(ii) From Eqs. (i) and (ii) $t_{1}: t_{2}=1: \sqrt{2}$