The thickness of the ice layer on the surface of lake is 20 m. A hole is made in the ice layer. What is the minimum length of the rope required to take a bucket full of water out ? (Take density of ice `= 0.9 xx 10^3 kg//m^3)`

Options

A. 2 m
B. 5 m
C. 9 m
D. 18 m

Answer

A

Explanation

(a) Given that density of ice ` = (9)/(10)xx` density of water, so only `(1)/(10)` the of ice will be outside the water. This means that `20 xx (1)/(10) = 2m`of ice layer will be above the water surface. In other words, in the hole, the water level will rise up to 18 m of the ice layer. So minimum length of rope required = 2m.