Ten one-rupeed coins are put on top of each other on a table. Each coin has mass $m$. The reaction of the $6^{th}$ coin (counted from the bottom) on the $7^{th}$ coins is .......... $mg$
$4$
$6 $
$7 $
$3 $
Find wrong statement
A uniform sphere of weight $W$ and radius $5\, cm$ is being held by a string as shown in the figure. The tension in the string will be
A uniform beam of weight $W$ is attached to a vertical wall by a hinge $H$ . The beam is held horizontal by a rope as shown below. Which one of the following best shows the direction of the reaction force $R$ at the hinge ?
The horizontal acceleration that should be given to a smooth inclined plane of angle $sin^{-1}\, (1/l)$ to keep an object stationary on the plane relative to the inclined plane is