MCQ
A tunnel has been dug through the centre of the earth and a ball is released in it. It will reach the other end of the tunnel after
- A$84.6$ minutes
- ✓$42.3$ minutes
- C$1$ day
- DWill not reach the other end
✓
Answer
Correct option: B.
$42.3$ minutes
b
(b) Ball execute $S.H.M.$ inside the tunnel with time period $T = 2\pi \sqrt {\frac{R}{g}} = 84.63\;\min $
Hence time to reach the ball from one end to the other end of the tunnel $t = \frac{{84.63}}{2} = 42.3\;\min .$
(b) Ball execute $S.H.M.$ inside the tunnel with time period $T = 2\pi \sqrt {\frac{R}{g}} = 84.63\;\min $
Hence time to reach the ball from one end to the other end of the tunnel $t = \frac{{84.63}}{2} = 42.3\;\min .$
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