Question

A balloon is filled with helium at sea level. The volume was measured to be 3.1 liters at a pressure of 0.97 atmosphere. If the balloon is released, it drifts upward. At a height of 4 kilometers, the pressure is measured to be 0.61 atmospheres. What is the volume of the balloon?

Answer 1

P1V1=P2V2 Boyle's law
0.97atm × 3.1L= 0.61atm × V2
V2= 4.9L

Answer 2

Answer:

The volume of the balloon is 4.92 L at the height of 4 km.

Explanation:

Initial Volume of the helium gas $V_1= 3.1 L$

Initial pressure of the helium gas $P_1= 0.97 atm$

Final volume of the helium gas = $V_2$

Final pressure of the helium gas =$P_2=0.61 atm$

Applying Boyle's law:

$P_1V_1=P_2V_2$ (At constant temperature)

$V_2=\frac{P_1\times V_1}{P_2}=\frac{0.97 atm\times 3.1 L}{0.61 L}$

$V_2=4.92 L$

The volume of the balloon is 4.92 L at the height of 4 km.