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Certain force acting on a 20 kg mass cha...

Certain force acting on a 20 kg mass changes its velocity from 5 `ms^(-1)` to 2 `ms^(1)`. Calculate the work done by the force.

Text Solution

Verified by Experts

Initial Kinetic energy `=(1)/(2)m u^(2) = (1)/(2) xx 20xx5^(2)=250J`
Final kinetic energy `=(1)/(2) mv^(2)`
`=(1)/(2)xx20xx2^(2)=40J`
Work done = change in Kinetic energy
`=250 - 40`
`=210J`
`20xx a[(2^(2)-5^(2))/(2a)]`
`20xx (-21)/(2)`
`=-210J`
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