A circular aluminium disc of radius is placed in a uniform magnetic field that varies…

PHYSICS · Single correct · A Level · Physics · Fields and their consequences · Fields and their consequences

Problem

A circular aluminium disc of radius

1.13\,\text{cm}

is placed in a uniform magnetic field that varies sinusoidally with peak value

0.20\,\text{T}

at a frequency of

50\,\text{kHz}

. The field is perpendicular to the plane of the disc. Find the peak value of the induced emf around the rim of the disc. (a)

50\,\text{V}

(b)

25\,\text{V}

(c)

17.7\,\text{V}

(d)

12.5\,\text{V}