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Is work energy theorem valid in non inertial frames?Explain

sudarshan gupta , 15 Years ago

Grade Upto college level

2 Answers

askIITianexpert IITDelhi

Last Activity: 15 Years ago

Yes,work energy theorem is valid in non-inertial frames also.Only we've to take care of the pseudo forces & work done by them(fictitious work though).For example as in dynamics problems Newton's laws are applied after taking appropriate pseudo forces in non-inertial frames so do we apply work energy theorem & count work done by these pseudo forces & their effect on energy.

While applying above theorem in centre of mass frame(non-inertial or accelerated) will not necessisate even this.

Pratham Ashish

Last Activity: 15 Years ago

yes, we can apply work energy theorm in non inertial frame provided we take into account the work done by the pseudo force also.

Take for simplicity a non inertial frame which has only transational acceleration 'α' .In this frame 2nd law will take the form

m*dv/dt = F - mα ,,,...now allpying the work energy theorm, we gat

0.5*m*(V_{²f - V²i )} = int(F.dr) - m *int(α.dr )

Thus in case of a non inertial force kinetic energy not only changes due to work done by material forces but also due to pseudo forces.....

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IIT – Delhi