When current passing through a coil increases, direction of induced emf is

Options

A. in the direction of existing current.
B. in the opposite direction of existing current
C. perpendicular to the flow of current.
D. indefinite

Answer

B

Explanation

Because self induced emf is given by
`epsilon=-L(dI)/(dt)`
Here current passing through the coil, increases with time and so `((dI)/(dt)) gt 0 rArr epsilon lt 0 rArr` self induced emf will be in a direction opposite to the flow of current, so that increase in the current through the coil can be opposed, according to Lenz.s law.