Electromagnetism - SS2 Physics Past Questions and Answers - page 5
According to Faraday's law of electromagnetic induction, the magnitude of the induced electromotive force (emf) is directly proportional to which of the following?
The strength of the magnetic field.
The area of the loop of wire.
The rate of change of magnetic flux through the loop of wire.
The resistance of the wire.
If a loop of wire is rotated within a uniform magnetic field, the induced current in the wire is maximised when the loop is:
Parallel to the magnetic field lines.
Perpendicular to the magnetic field lines.
Aligned at a 45-degree angle to the magnetic field lines.
None of the above.
When a conductor is moved through a magnetic field, the magnitude of the induced emf can be increased by:
Decreasing the speed of the conductor.
Increasing the magnetic field strength.
Decreasing the length of the conductor.
Increasing the resistance of the conductor.
A coil of wire is connected to a resistor. If the coil is moved back and forth within a magnetic field, what happens to the brightness of the bulb connected to the resistor?
The brightness decreases as the coil moves back and forth.
The brightness increases as the coil moves back and forth.
The brightness remains constant regardless of the coil's motion.
The brightness depends on the resistance of the coil.
A magnetic field of 0.5 T is directed perpendicular to a circular loop with a radius of 0.1 m. If the magnetic field decreases to zero in 0.2 seconds, what is the magnitude of the induced emf in the loop?
A coil with 200 turns is placed in a uniform magnetic field of 0.8 T. If the flux through the coil changes at a rate of 50 T·m2/s, what is the magnitude of the induced emf in the coil?