Question

A vertical U-tube of uniform cross section contains mercury in both sides of its arms as shown in figure.
Glycerin column of $10cm$ is introduced into one of its arms. Oil of density $0.8g/cc$ is poured into the other arm until the upper surface of the oil and glycerin at the same horizontal level.
( ${\rho }_{Hg}=13.6g/cc,{\rho }_{pressure}=1.3g/cc$)
The length of coil column is

• A. $10.4cm$
• B. $8.2cm$
• C. $7.2cm$
• D. $9.6cm$

Answer 1

The correct option is D $9.6cm$

$\text{Pressure at point A}andB\text{same.}$

$P_A=P_B$

$P_0+1.3\times g\times 10=P_0+0.8\times g\times h+13.6\times g\times (10-h)$

$13=0.8h+136-13.6h$

$12.8h=123$

$h=9.6cm$

$\text{Answer:}\left(D\right)$