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.
(a) Which marble will surely reach the next peak?
(b) Along which path/s the mechanical energy will be conserved?
(c) Along which path/s is the law of conservation of energy obeyed?
(a) Marble A will surely reach the next peak because there will be no energy loss on the frictionless path.
(b) Mechanical energy will be conserved along Path 1.
(c) Since energy cannot be created or destroyed, the law of conservation of energy applies to both scenarios.
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