A `10 kg` boy standing in a `40 kg` boat floating on water is `20 m` away from the shore of the river. If the boy moves `8 m` on the boat towards the shore, then how far is he from the shore ? (Assume no friction between boat and water).

Explanation

Mas of the boy (m) = 10 kg Mass of the boat (M) = 40 kg Distance travelled by boy (l) = 8m
Distance travelled by the boat in opposite
direction ` = (ml)/(M=m) = (10 xx 8)/(10+40) = 1.6 m `
Distance of the boy from the shore is
`(20-8) + (1.6) = 13.6 m `