question_answer

A moving body of mass 10 kg has 20 Joules of kinetic energy. Calculate its speed.

Answer:

Given,   \[m=10kgK.E.=20J\]                 \[v=?\] We know, \[K.E.=\frac{1}{2}m{{v}^{2}}\] \[\Rightarrow {{V}^{2}}=\frac{2\times K.E.}{m}\Rightarrow V=\sqrt{\frac{2\times K.E.}{m}}\] \[\therefore \,\,V=\sqrt{\frac{2\times 20}{10}}=\sqrt{4}=2\,m/s\]