Answer to Question #113969 in Physics for Arvin

Question

The diameter of an approximately spherical May Day ball is 35 cm. The balloon is filled with helium so that the balloon has an overpressure of 0.12 bar at a temperature of 18°C. What is the mass of helium in the sphere?

Answer 1

$$pV=\frac{m}{M}RT\to \frac{4}{3}\pi r^3p=\frac{m}{M}RT$$

$$\frac{4}{3}\pi (0.35)^3(0.12\cdot 10^5)=\frac{m}{4}(8.31)(273+18)$$

$$m=3.6\ g$$