Question

A block is pushed up a rough inclined plane of ${45}^o$. If the time of decent is twice the time of ascent, the coefficient of friction is

• A. 0.6
• B. 0.4
• C. 0.5
• D. 0.25

Answer 1

The correct option is A 0.6

: $ta=2ta$

$\mu =\tan \theta \left[\frac{n^2-1}{n^2+1}\right]$

$\mu =\tan 45\left[\frac{n^2-1}{n^2+1}\right]$

$\mu =0.6$.