A ball floats on surface of water in a container exposed to the atmosphere. Will the ball remain immersed at its depth or will it sink or will it rise if the container is covered and the air is removed?
Correct answer: C. The ball remains immersed at its former depth
- A. The ball sinks
- B. The ball rises
- C. The ball remains immersed at its former depth
- D. It oscillates
Explanation
The correct answer is Option C: The ball remains immersed at its former depth. When the container is covered and the air is removed, the atmospheric pressure above the water surface is reduced, but this does not affect the buoyant force acting on the ball. The buoyant force depends on the volume of water displaced by the ball, which remains unchanged. Therefore, the ball remains at the same depth.Option A is incorrect because the removal of air does not decrease the buoyant force to cause the ball to sink. Option B is incorrect as the buoyant force does not increase to make the ball rise. Option D is incorrect because there is no change in forces that would cause the ball to oscillate.
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