InterviewSolution
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rt is tied to the end of an unsireichedA toy cart isstring oF leng Lmoves in horizontal circle co ith Tadidsr2」,andime period T. T it is stretehed Speeded untilit moves in horizon tel circle 아 rd dius '84,aimperiod Tn relation beth Tand-互is C Hookslaud obeyedcohen revolved the toy carJE IT2 |
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Answer» The new time period is given by T₁ = √3T/2 Explanation: Case I string length = l string is stretched to 2l, so net increase in length = 2l - l = l => spring force, F = kl where k = spring constant when the string is rotated with 2l radius, we know that centripetal force is given by, F = mrω² = m x 2l x (2π/T)² Since the centripetal force and spring force should be equal, hence, kl = m x 2l x (2π/T)² => k = 2m x (2π/T)².............eq1 Case II string length = l string is stretched to 3l, so net increase in length = 3l - l = 2l => spring force, F = k x 2l = 2kl when the string is rotated with 3l radius, we know that centripetal force is given by, F = mrω₁² = m x 3l x (2π/T₁)² Since the centripetal force and spring force should be equal, hence, 2kl = m x 3l x (2π/T₁)² => k = 3m/2 x (2π/T₁)².............eq2 equating eq1 and eq2 we get: 2m x (2π/T)² = 3m/2 x (2π/T₁)² => T₁²/T² = 3/4 => T₁ = √3T/2 Hence the new time period is given by T₁ = √3T/2 hit like if you find it useful |
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