﻿   A simple pendulum of length L and with a bob of mass M is oscillating in a plane about a vertical line between angular limits –Ï• and +Ï•. For an angular displacement θ (< Ï•) the tension is the string and the velocity of the bob are T and v respectively. The flowing relations hold good under the above conditions: : Kaysons Education

# A Simple Pendulum Of Length L and With A Bob Of Mass M is Oscillating In A Plane About A Vertical Line Between Angular Limits –Ï• and +Ï•. For An Angular Displacement θ (< Ï•) The Tension Is The String And The Velocity Of The Bob Are T and v respectively. The Flowing Relations Hold Good Under The Above Conditions:

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## Question

### Solution

Correct option is

& The magnitude of the tangential acceleration of the bob

As shown in fig, the resultant force F = T – M g cos θ provides the centripetal force  for the circular motion of the bob. When

T = cos θ = Mg, . The resultant force would then be  and there would be no centripetal force available for the circular motion of the bob. Tangential acceleration of the bob is

caused by the component of Mg in a

direction perpendicular to the string.

The component is Mg sin θ. If the

acceleration is , we have

If T = Mg cos θ, there will be no resultant

force F along the string and hence

there will be no centripetal force.

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