A Pendulum bob of mass m and charge q is suspended by a thread of length l. The pendulum is placed in a region of a uniform electric field E directed vertically upward. If the electristatic force acting on the sphere is les than that of gravitational fore, calculate the period with which the pendulum oscillates (Assumes small oscillation)

A Pendulum bob of mass m and charge q is suspended by a thread of leng

1.	A Pendulum bob of mass m and charge q is suspended by a thread of length l. The pendulum is placed in a region of a uniform electric field E directed vertically upward. If the electristatic force acting on the sphere is les than that of gravitational fore, calculate the period with which the pendulum oscillates (Assumes small oscillation)
Answer» `T=2pisqrt(L/(g+(qE)/m))` `T=2pisqrt(l/(g-(qE)/m))` `T=pisqrt(l/(g-(qE)/m))` `T=pisqrt(l/(g+(qE)/m))` Solution :(B) Resultant force vertically DOWNWARDS `(mg-qE)` Net acceleration `g'=(g-(qE)/m)` `T=2pisqrt((l/(g')))` `T=2pisqrt(l/((g-(qE)/m)))`

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