If the magnetic field strength is doubled, what happens to the induced EMF in a
Practice Questions
Q1
If the magnetic field strength is doubled, what happens to the induced EMF in a coil with a constant number of turns and area?
It doubles
It halves
It remains the same
It quadruples
Questions & Step-by-Step Solutions
If the magnetic field strength is doubled, what happens to the induced EMF in a coil with a constant number of turns and area?
Correct Answer: Induced EMF will also double.
Step 1: Understand that EMF (electromotive force) is generated in a coil when there is a change in magnetic flux.
Step 2: Recall that magnetic flux is calculated as the product of the magnetic field strength (B), the area of the coil (A), and the cosine of the angle (θ) between the magnetic field and the normal to the surface of the coil.
Step 3: Note that if the magnetic field strength (B) is doubled, the magnetic flux through the coil also doubles, assuming the area (A) and angle (θ) remain constant.
Step 4: According to Faraday's law, the induced EMF is directly proportional to the change in magnetic flux.
Step 5: Since the magnetic flux has doubled, the induced EMF will also double.
Faraday's Law of Electromagnetic Induction – The induced EMF in a coil is proportional to the rate of change of magnetic flux through the coil.
Magnetic Flux – Magnetic flux is the product of the magnetic field strength, the area of the coil, and the cosine of the angle between the magnetic field and the normal to the coil's surface.
Induced EMF – Induced EMF is the voltage generated in a coil due to a change in magnetic flux.
