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CBSE Class 9 Answered

Consider I lifted an iron bar from the ground and held it above my head.It has potential energy.If I let go of the iron bar the potential energy gets converted into kinetic energy.What if instead of letting it fall,I keep it back on the ground.Where does the potential energy acquired by the iron bar when I lifted it go,i.e what happens to the gravitational potential energy in an object if the work it was supposed to do was done by an external force.
Asked by | 05 Mar, 2013, 09:19: PM
answered-by-expert Expert Answer
Here since you will be doing the work, that potential energy is used by your muscles.
Energy is always conserved, we have to understand its flow as energy is not only in the form of KE and PE.
Answered by | 13 Mar, 2013, 01:05: AM

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