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Question
Two objects having equal masses are moving with uniform velocities of 2 m/s and 6 m/s respectively. Calculate the ratio of their kinetic energies.
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Solution
Let the masses of the two bodies be (m1) = m kg and (m2) = m kg.
Velocity of the first body, (v1) = 2 m/s
Velocity of the first body, (v2) = 6 m/s
The required ratio is-
= `("kinetic energy")_1/("Kinetic energy")_2`
= `(1/2(m_1) (v_1)^2)/(1/2(m_2) (v_2)^2)`
= So , put the values to get the ratio ,
= `(2)^2/(6)^2`
= `1/9`
The ratio of the kinetic energies is, K.E of body 1 : K.E of body 2 = 1 : 9
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