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प्रश्न
State the condition under which the mechanical energy is conserved.
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उत्तर
Mechanical energy is conserved only when there are no frictional forces for a given system (i.e., between the body and the air). Thus, conservation of mechanical energy is strictly valid only in vacuum, where friction due to air is absent.
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संबंधित प्रश्न
Show that the sum of kinetic energy and potential energy (i.e., total mechanical energy) is always conserved in the case of a freely falling body under gravity (with air resistance neglected) from a height h by finding it when
- The body is at the top.
- the body has fallen a distance x.
- the body has reached the ground.
State whether the object possess kinetic energy, potential energy, or both :
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State whether the object possess kinetic energy, potential energy, or both :
A flying aeroplane _______________.
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A stretched rubber band _____________
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(i) A ball thrown upwards.
(ii) A stone dropped from the roof of a building.
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