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A bob of mass m is suspended by a light string of length L. It is imparted a horizontal velocity vo at the lowest point. IT COMPLETES A SEMI CIRCULAR TRAJECTORY IN VERTICAL PLANE..... REFER TO ATTACHMENT. |
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Answer» re two external forces on the bob: Gravity and teñsion.The teñsion does no work as DISPLACEMENT is always PERPENDICULAR to stŕing.Total mechànical energy of the system is consèrved Energy = EGravity = mgTēnsion = TTaking potențial energy of the system to be at zēro at loweśt point A, THENAT A, From Newton's second law,TA(tenšion at A) - mgAt highest point C, the string slaćks as tension at C becomes zero.C,Let Vc be velocity at C THENFROM Newtons second law, from iv we get From iiiUsing I,orAT B, orThusThe ratio of KINETIC energy at B and C is━━━━━━━━━━Now checking the options we get |
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