Question

Two glass bulbs A and B are connected by very small tube having a stop cock. Bulb A has a volume of 100 ml and contained the gas while bulb B was empty and has a volume of 150 ml. On opening the stop cock, the pressure of the gas in bulb A will fall down to___.

• A. 80%
• B. 60%
• C. 40%
• D. 20%

Answer 1

The correct option is C

40%

The total pressure $P_T=\frac{P_1{V}_1+P_2{V}_2}{V_1+V_2}$

$V_1=100ml{V}_2=150ml$

$P_1=P{P}_2=0(\because itisempty$)

$P_T=\frac{100\times P+150\times 0}{100+150}=\frac{100}{250}P=0.4P$

The pressure of the bulb ' A' will be fall down to 40%.