A string is wrapped around a cylinder of mass `M` and radius `R`. The string is pulled vertically upwards to prevent the centre of mass from falling as the cylinder unwinds the string. The tension in the string isA. `(Mg)/6`B. `(Mg)/3`C. `(Mg)/2`D. `(2Mg)/3`

A string is wrapped around a cylinder of mass `M` and radius `R`. The

1.	A string is wrapped around a cylinder of mass `M` and radius `R`. The string is pulled vertically upwards to prevent the centre of mass from falling as the cylinder unwinds the string. The tension in the string isA. `(Mg)/6`B. `(Mg)/3`C. `(Mg)/2`D. `(2Mg)/3`
Answer» Correct Answer - B Equation of motion `Mg-T=Ma` ………….i Taking torque about the axis passing through the centre of the spool and perpendicular to it `TR=Ialpha=1/2MR^(2)(a/2)` `T=1/2Ma` …………ii From eqn i and ii `Ma=Mg-1/2ma` `a=(2g)/3` `:. T=(Mg)/3`

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A string is wrapped around a cylinder of mass `M` and radius `R`. The string is pulled vertically upwards to prevent the centre of mass from falling as the cylinder unwinds the string. The tension in the string isA. `(Mg)/6`B. `(Mg)/3`C. `(Mg)/2`D. `(2Mg)/3`

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