Ten one-rupee coins are put on top of each other on a table. Each coin has a mass m . Give the magnitude and direction of
(a) the force on the `7^(th)` coin (counted from the bottom due to all the coins on its top .
(b) the force on the `7^(th)` coin by the eigth coin.
(c ) the reaction of the `6^(th)` coin one th `7^(th)` coin .

Explanation

(a) 3 m g (down) (b) 3 m g (down) (c) 4 m g (up)