Q. 44.3( 37 Votes )

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

Answer :

Given that ,

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

K.E.=1/2×(m×v^{2})

1/2×(50×v^{2}) = 625

v^{2} =(625 × 2)/50=1250/50=25

v = √25= 5 m/s Ans

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