A hot-air balloon contains air at a temperature of 180 oF. The surrounding air has a temperature of 60 oF. The radius of the spherical balloon is 30.6 ft. The weight of the empty balloon is 200lb. Determine the maximum load (in lbf) that the balloon can lift. Use thermodynamic tables to obtain the density of the hot-air and surrounding air.

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