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प्रश्न
Can any object have mechanical energy even if its momentum is zero? Explain.
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उत्तर
Yes, if momentum of an object is zero, i.e.; p = mv = 0
which gives v = 0 as m ≠ 0
Kinetic energy of the object = `1/2"mv"^2` = 0
Now, Mechanical energy = potential energy + kinetic
energy (= 0) – potential energy (∴ K. E = 0)
So any object can have mechanical energy even if its momentum is zero.
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