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Question
Two identical marbles A and B are rolled down along Path 1 and Path 2 respectively.
Path 1 is frictionless and Path 2 is rough.
- Which marble will surely reach the next peak?
- Along which path/s the mechanical energy will be conserved?
- Along which path/s is the law of conservation of energy obeyed?
Solution
- Path 2 is rough, and Path 1 is frictionless. Because there will be no energy lost on the frictionless road, marble A will undoubtedly reach the top.\
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Total mechanical energy = kinetic energy (k) + potential energy (u)
When there is no frictional force, it remains constant; hence, mechanical energy will be preserved along path 1.
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Since energy cannot be created or destroyed, the law of conservation of energy applies to both scenarios.
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