A bullet moving with a speed of 100 ms^(...

A bullet moving with a speed of `100 ms^(-1)` can just penetrate into two planks of equal thickness. Then the number of such planks, if speed is doubled will be .

`6`

`10`

`4`

`8`

Text Solution

Verified by Experts

The correct Answer is:

`F =` resistance is same
`1/2mv^(2) =n(F.d)`
`rArr n prop v^(2)`
if `v` is doubled, n will become four times.

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