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Question
Two bodies of equal masses are moving with uniform velocities v and 2v. Find the ratio of their kinetic energies.
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Solution
K.E = `1/2 mv^2`
K.E = `1/2 m (2v)^2`
K.E = `(1/2 mv^2) xx 4`
∴ Ratio of their K.E = `(1/2 mv^2)/(4(1/2 mv^2))`
= `1/4`
= 1 : 4
Ratio of K.E. of A and B is 1 : 4.
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