Question

A particle slides down a smooth inclined plane of elevation α fixed in an elevator going with an acceleration ‘a’. The base of the incline has a length ‘L’. the time taken by the particle to reach the bottom is

• A.
• B.
• C.
• D.

Answer 1

The correct option is B

$S_{\gamma }=\frac{L}{cos\alpha }{A}_{\gamma }=(g+a)sin\alpha$

$S=ut+\frac{1}{2}a{t}^2$

$\therefore \frac{L}{cos\alpha }=0+\frac{1}{2}(g+a)sin\alpha .t^2\Rightarrow t={\left(\frac{2L}{(g+a)sin\alpha cos\alpha }\right)}^{\frac{1}{2}}$