MCQ
Two balls are dropped from heights $h$ and $2h$ respectively from the earth surface. The ratio of time of these balls to reach the earth is
- ✓$1:\sqrt 2 $
- B$\sqrt 2 $ $: 1$
- C$2:1$
- D$1:4$
✓
Answer
Correct option: A.
$1:\sqrt 2 $
a
(a)$t = \sqrt {\frac{{2h}}{g}} \Rightarrow \frac{{{t_1}}}{{{t_2}}} = \sqrt {\frac{{{h_1}}}{{{h_2}}}} = \sqrt {\frac{1}{2}} = \frac{1}{{\sqrt 2 }}$
(a)$t = \sqrt {\frac{{2h}}{g}} \Rightarrow \frac{{{t_1}}}{{{t_2}}} = \sqrt {\frac{{{h_1}}}{{{h_2}}}} = \sqrt {\frac{1}{2}} = \frac{1}{{\sqrt 2 }}$
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