Question

A beaker containing a liquid is kept inside a big closed jar. If the air inside the jar is continuously pumped out. The pressure in the liquid near the bottom of the liquid will

(a) increase

(b) decrease

(c) remain constant

(d) First decrease and then increase.

Answer 1

Answer ⇒ Option (b). Decreases.

Explanation ⇒ When there is an air, then, Pressure at the bottom of the jar will be given by,

  P = P₀ + hρg, where h is the depth of bottom.

Now, when air is pumped out, then, there will be no atmospheric pressure, hence, P₀ will be zero.

Thus, New Pressure,

P' = hρg

This Means, P = P' + P₀

Hence, Pressure at first case was greater than second by P₀.

Thus, we can say that pressure at bottom is decreased when air is pumped out.

Hope it helps.

Answer 2

Hi there.. Your answer is option B. (decreases).

By formula P=P'+ pgh (p= rho)

U can get ur answer..