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प्रश्न
The casing of a rocket in flight burns up due to friction. At whose expense is the heat energy required for burning obtained? The rocket or the atmosphere?
उत्तर
The heat energy needed for the burning of the rocket's casing is sourced from the rocket itself. Due to the work done against friction, the rocket’s kinetic energy is continually reduced; this energy expended against friction then re-emerges as heat energy.
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