A bubble of a gas released at the botton of a lake increases to eight times its original volume when it reaches the surface. Assuming that atmospheric pressure is equivalent to the pressure exerted by a column of water 10 m height, the depth of the lake is

A bubble of a gas released at the botton of a lake increases to eight

1.	A bubble of a gas released at the botton of a lake increases to eight times its original volume when it reaches the surface. Assuming that atmospheric pressure is equivalent to the pressure exerted by a column of water 10 m height, the depth of the lake is
Answer» 80 m 90 m 40 m 70 m Solution :As VOLUME of the bubble at the surface becomes 8 times, pressure at the bottom of the lake is 8 times the pressure at the surface. As pressure on the surface =1 atm., pressure at the bottom =8 atm. Thus, pressure due to depth of the lake =7 atm=70 m of WATER.