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Question
A body of mass 50 kg has a momentum of 3000 kg−1 ms. Calculate:
(j) the kinetic energy of the body.
(ii) the velocity of the body.
Solution
(i) m = 50 kg, p = 3000 kg ms−1
p = mv
v = `"P"/"m"=3000/50` = 60 ms−1
Kinetic energy of the body =`1/2` mv2
`=1/2xx50xx(60)^2` = 25 × 3600
= 90000 J
(ii) Velocity of the body v = 60 ms−1
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