A rectangular metal loop ABCD of is passed through the magnetic field with a constant velocity v. Which of the following represents power (P) dissipated vs time (t) graph?
1. 2.
3. 4.
Self-inductance of a solenoid is 5 mH. If the current is decreasing through it at the rate 10+3 A/s, then emf induced in the solenoid is
1. -5V
2. 5V
3. 2.5V
4. -2.5V
Keeping number of turns constant self inductance L of a solenoid varies with its length l as
1. Ll
2. L
3. L
4. L
A conducting rod AC of length 4l is rotated with angular velocity about a point O in a uniform magnetic field directed into the plane of the paper. If AO = l and OC = 3l, then the potential difference between A and C, VA - VC is
1.
2.
3.
4.
A flexible wire bent in the form of a circle is placed in a uniform magnetic field perpendicular to the plane of the circle. The radius r of the circle changes with time t as shown in the figure. The graph of the magnitude of induced emf versus time t in the circle is represented by
1. 2.
3. 4.
A cylindrical space of radius R is filled with a uniform magnetic induction B parallel to the axis of the cylinder. If B changes at a constant rate, the graph showing the variation of the induced electric field with distance r from the axis of the cylinder is
1. 2.
3. 4.
A long conducting wire AH is moved over a conducting triangular wire CDE with a constant v in a uniform magnetic field directed into the plane of the paper. Resistance per unit length of each wire is r. Then
1. A clockwise induced current will flow in the closed-loop.
2. No induced current will flow in the closed-loop.
3. Induced current in the closed-loop alternately changes its direction.
4. An anticlockwise induced, the current will flow in the closed-loop.
The figure below shows a square loop of side 0.5 m and resistance 10 . The magnetic field has a magnitude B = 1.0 T. The work done in pulling the loop out of the field slowly and uniformly in 2 seconds is
1. 3.125
2. 6.25
3. 1.25
4. 5.0
The wires \(\mathrm{P}_1\mathrm{Q}_1\) and \(\mathrm{P}_2\mathrm{Q}_2\) are made to slide on the rails with the same speed \(10~\text{m/s}\). If \(\mathrm{P}_1\mathrm{Q}_1\) moves towards the left and \(\mathrm{P}_2\mathrm{Q}_2\) moves towards the right, then the electric current in the \(19~\Omega\) resistor is:
1. zero
2. \(10~\text{mA}\)
3. \(0.1~\text{mA}\)
4. \(1~\text{mA}\)
The triangular circuit ABC shown in the figure is in a very long solenoid of radius R such that the plane of the triangular circuit is normal to the length of the solenoid. If the magnetic field changes at the rate dB/dt, then the induced emf in the triangular circuit is
1.
2.
3.
4.