Question

An induced emf is produced when a magnet is plunged into a coil. The magnitude of induced emf is independent of

Answer 1

induced emf=NΔϕΔtinduced emf=NΔϕΔt.

where,ϕϕ is the magnetic flux through the coil.

The flux, ϕϕ depends on both the area of the coil, the magnetic field through the coil and the angle between the direction of magnetic field and the area vector of the coil ( area vector is perpendicular to the plane of the coil ). And the equation of magnetic flux goes as ϕϕ = BAcosθθ. The flux through a coil is changed by changing any one of these parameters.So, the flux has a direct relation to the area of the coil.

A core can increase the magnetic field to many times the strength of the actual field through the coil alone, due to the "magnetic permeability μμ " of the material where μμ depends on the "Magnetic strength of the core material". Hence, B depends on the magnetic strength of the core material also.Hence, the magnetic flux too

Hope it helps you.