Question

A bucket contains water filled upto a height$=15cm$. The bucket is tied to a rope which is passed over a frictionless light pulley and the other end of the rope is tied to a weight of mass which is half of that of the (bucket + water). The water pressure above atmosphere pressure at the bottom is

• A. $0.5kPa$
• B. $1kPa$
• C. $5kPa$
• D. None of these

Answer 1

Answer: (B)

$1kPa$

Let $T$ be the tension in the rope.

For the bucket, $Mg-T=Ma$

For the weight, $T-\frac{Mg}{2}=\frac{Ma}{2}$

Hence, $a=\frac{g}{3}$

Thus the effective gravitational force acting on water filled in the bucket $=g-\frac{g}{3}=\frac{2g}{3}$

Pressure at the bottom $=h\rho g_{eff}=h\rho \left(\frac{2g}{3}\right)=1kPa$