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प्रश्न
In an elastic collision
विकल्प
the initial kinetic energy is equal to the final kinetic energy
the final kinetic energy is less than the initial kinetic energy
the kinetic energy remains constant
the kinetic energy first increases then decreases.
उत्तर
the initial kinetic energy is equal to the final kinetic energy
As no energy is lost into heat in an elastic collision, the initial kinetic energy is equal to the final kinetic energy.
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