How Fast Should a Boy Weighting 30 Kg Run So that His Kinetic Energy is 375 Joule?

How fast should a boy weighting 30 kg run so that his kinetic energy is 375 joule?

Numerical

We know that , K.E = `1/2` mv²

375 = `1/2` x 30 x v²

or v² = `(375 xx 2)/30` = 25 m/s

or v = 5 m/s

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Chapter 1: Force, Work, Energy and Power - Exercise 4 [Page 59]

Chapter 1 Force, Work, Energy and Power
Exercise 4 | Q 9 | Page 59

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