The current in an inductor of self-inductance \(4~\text{H}\) changes from \(4~ \text{A}\) to \(2~\text{A}\) in \(1~ \text s\). The emf induced in the coil is:
1. \(-2~\text{V}\)
2. \(2~\text{V}\)
3. \(-4~\text{V}\)
4. \(8~\text{V}\)
1. | \(\left[M^2LT^{-2}A^{-2}\right]\) | 2. | \(\left[MLT^{-2}A^{2}\right]\) |
3. | \(\left[M^{2}L^{2}T^{-2}A^{2}\right]\) | 4. | \(\left[ML^{2}T^{-2}A^{-2}\right]\) |
1. | \(10~\text{J}\) | 2. | \(2.5~\text{J}\) |
3. | \(20~\text{J}\) | 4. | \(5~\text{J}\) |
The magnetic flux linked to a circular coil of radius \(R\) is given by:
\(\phi=2t^3+4t^2+2t+5\) Wb.
What is the magnitude of the induced EMF in the coil at \(t=5\) s?
1. \(108\) V
2. \(197\) V
3. \(150\) V
4. \(192\) V
Kamla peddles a stationary bicycle. The pedals of the bicycle are attached to a \(100\) turn coil of an area of \(0.10~\text{m}^2\). The coil rotates at half a revolution per second and it is placed in a uniform magnetic field of \(0.01~\text{T}\) perpendicular to the axis of rotation of the coil. What is the maximum voltage generated in the coil?
1. \(0.628~\text{V}\)
2. \(0.421~\text{V}\)
3. \(0.314~\text{V}\)
4. \(0\)
The ratio of magnetic energy per unit volume and electrostatic energy stored per unit volume in a parallel plate capacitor is:
1. \(\left(\dfrac{1}{\varepsilon_0 \mu_0}\right)\dfrac{B^2}{E}\)
2. \(\left(\dfrac{1}{\varepsilon_0 \mu_0}\right)\dfrac{E^2}{B}\)
3. \(\left(\dfrac{1}{2\varepsilon_0 \mu_0}\right)\dfrac{B^2}{E}\)
4. \(\left(\dfrac{1}{2\varepsilon_0 \mu_0}\right)\dfrac{E^2}{B}\)