Question

Bob of simple pendulum of length l is made of iron.The pendulum is oscillating over a horizontal coil carrying direct current.If time period of pendulum is T then:
T<2π√l/g and damping is larger than in air alone...
How?

Answer 1

@Michele_Laino sir

Answer 2

please can you make a drawing of that pendulum?

Answer 3

here is my reasoning:
the situation can be represented by this drawing:

we have a magnetic force directed upward, so the period of oscillation is less than the case in absence of wire

Answer 4

oops.. I meant the period is greater than the case in absence of wire.
when the velocity is reversed we have a magnetic force downward, and the period is less than the case in absence of wire