select all the correct answers.\nin which situations is work being done?\n□ hannah leans against her locker…

select all the correct answers.\nin which situations is work being done?\n□ hannah leans against her locker, but it doesnt move.\n□ andys car rolls down a hill with the engine off.\n□ a wind turbine stands still on a sunny, windless day.\n□ a balloon expands as it is heated by the sun.\n□ james pedals a stationary exercise cycle that doesnt move.

select all the correct answers.\nin which situations is work being done?\n□ hannah leans against her locker, but it doesnt move.\n□ andys car rolls down a hill with the engine off.\n□ a wind turbine stands still on a sunny, windless day.\n□ a balloon expands as it is heated by the sun.\n□ james pedals a stationary exercise cycle that doesnt move.

Answer

Brief Explanations:

Work is done when a force causes an object to move in the direction of the force. In the case of Hannah leaning against the locker with no movement, no work is done as there is no displacement. For the wind - turbine standing still, there is no work as there is no motion. For James pedaling a stationary cycle, although he is applying a force, the cycle doesn't move, so no work is done. When Andy's car rolls down a hill, gravity is doing work on the car as it moves in the direction of the gravitational force. When a balloon expands due to heating by the Sun, the gas inside the balloon is doing work on the walls of the balloon as it causes a change in volume (displacement of the balloon's surface).

Answer:

B. Andy's car rolls down a hill with the engine off. D. A balloon expands as it is heated by the Sun.