## Motion in a vertical circle and conservation of energy

A stone  tied to a string of length l is whirled around a vertical circle with the other end of the string at the centre. At a certain instant of time the stone is at the lowest position and has a speed u. What is the magnitude of change in its velocity as it reaches […]

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## Is law of conservation of energy violated here?

“When a body is moving with uniform speed on a rough surface under the application of a constant external force and an equal and opposite frictional force, the work done by both the forces should be equal. as a result, the net work done by both the forces should be zero. however, we find that […]

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## Interference is in complete agreement to law of conservation of energy

Tilak gurjar posted; “Interference is in complete agreement to law of conservation of energy. Comment” Answer: If there were no interference, the resultant intensity at a point illuminated by two sources will be I = I1+I2 Due to interference This shows that energy is conserved even after interference. There is only a redistribution of energy. There […]

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## Physics doubts from Class XI student

How to check the correctness of equation s=u+0.5a(2n-1) using dimensional analysis?(Please describe) In law of conservation of linear momentum derivation,why force acting on body B by A is taken as product of mass and acceleration of "B" and not "A" instead of "B"?   Answer The accuracy is checked as usual, but remember that the […]