MCQ
A boy throws balls into air at regular interval of $2$ second. The next ball is thrown when the velocity of first ball is zero. How high do the ball rise above his hand is ...... $m$ [Take $g=9.8 \,m / s ^2$ ]
- A$4.9$
- B$9.8$
- ✓$19.6$
- D$29.4$
✓
Answer
Correct option: C.
$19.6$
c
(c)
(c)
$2 T=\frac{2 u}{g} \Rightarrow 2=\frac{u}{9.8} \Rightarrow u=19.6$
$H=\frac{u^2}{2 g}=\frac{19.6 \times 19.6}{2 \times 9.8}$
$\Rightarrow H=19.6 \,m$
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