A spherical balloon is made from a material whose mass is 2.27 kg. The thickness of the material is negligible compared to the 2.25-m radius of the balloon. The balloon is filled with helium (He) at a temperature of 291 K and just floats in air, neither rising nor falling. The density of the surrounding air is 1.19 kg/m3. Find the absolute pressure of the helium gas.

In a system with only a single force acting upon a body, what is the relationship between the change in kinetic energy and the work done by the force? answers: work is equal to the change in kinetic energy.work depends on the square of the change in potential energy.work is equal to the negative of the change in kinetic energy.work is equal to the square of the change in kinetic energy