A circular loop of radius R carrying current I lies in the x-y plane with its centre at the origin. The total magnetic flux through the x-y plane is
(1) Directly proportional to I
(2) Directly proportional to R
(3) Directly proportional to R2
(4) Zero
A circular disc of radius \(0.2\) m is placed in a uniform magnetic field of induction \(\frac{1}{\pi} \left(\frac{\text{Wb}}{\text{m}^{2}}\right)\) in such a way that its axis makes an angle of \(60^{\circ}\) with \(\vec {B}.\) The magnetic flux linked to the disc will be:
1. | \(0.02\) Wb | 2. | \(0.06\) Wb |
3. | \(0.08\) Wb | 4. | \(0.01\) Wb |
The primary and secondary coils of a transformer have \(50\) and \(1500\) turns respectively. If the magnetic flux \(\phi\) linked with the primary coil is given by \(\phi=\phi_0+4t,\) where \(\phi\) is in Weber, \(t\) is time in seconds, and \(\phi_0\) is a constant, the output voltage across the secondary coil is:
1. \(90~\mathrm{V}\)
2. \(120~\mathrm{V}\)
3. \(220~\mathrm{V}\)
4. \(30~\mathrm{V}\)
The sun delivers of electromagnetic flux to the earth's surface. The total power that is incident on a roof of dimensions 8 m20 m will be
(1) (2)
(3) (4)