Q4 of 49 Page 11

How fast should a man of 50 kg run so that his kinetic energy will be 625 J?

Given that ,

m(mass)= 50 kg and K.E.(kinetic energy) = 625 j

As we know that:-

K.E.=1/2×(m×v2) 

1/2×(50×v2) = 625

v2 =(625  × 2)/50=1250/50=25

v = √25= 5 m/s            Ans

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