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Question
If the mass as well as the velocity of a body is doubled then the kinetic energy of the body ______ the initial kinetic energy.
Options
is doubled
becomes eight times
becomes four times
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Solution
If the mass as well as the velocity of a body is doubled then the kinetic energy of the body becomes eight times the initial kinetic energy.
Explanation:
Kinetic energy is given by KE = `1/2`mv2
If mass and velocity are both doubled, the new kinetic energy becomes:
KE' = `1/2(2m)(2v)^2`
= 8 × initial K.E.
So, the kinetic energy becomes eight times the initial value.
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