Question

A simple U tube contains mercury to the same level in both of its arms. If water is poured to a height of $13.6cm$ in one arm, The rise in mercury level in the other arm is x cm.Then x=?
Given : density of mercury = $13.6\times {10}^{3}kg{m}^{-3}$ and density of water = ${10}^{3}kg{m}^{-3}$

• A. 13.6 cm
• B. 10 cm
• C. 1 cm
• D. 1.36 cm

Answer 1

The correct option is C 1 cm

The Pressure exerted by both mercury and water should be same
$P_w=P_m⟹{\rho }_{w}g{h}_w={\rho }_{m}g{h}_m$

$\Rightarrow {10}^3\times 10\times 0.136=13.6\times {10}^3\times 10\times h_m$

$\therefore h_m=1cm$