Q. A small block of mass $m$ rests on a smooth wedge of angle $\theta$. With what horizontal acceleration $a$ should the wedge be pulled, as shown in figure, so that the block falls freely?

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A

$g \cos \theta$

B

$g \sin \theta$

C

$g \cot \theta$

D

$g \tan \theta$

Solution:

$\tan \theta=\frac{g}{a} $
$\Rightarrow a=g \cot \theta$

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