NEET Electromagnetic Induction — Set 14

Question 1

A metal ring is placed near a solenoid. When an AC current flows through the solenoid, the ring experiences a force. This is primarily due to what?

Accepted Answer

The AC current creates a varying magnetic field, inducing currents in the ring that generate an opposing field, leading to a repulsive or attractive force based on Lenz’s law.

Question 2

A rectangular loop of sides 30 cm and 12 cm moves out of a 0.6 T field at 1 m/s perpendicular to the shorter side. What is the motional emf?

Accepted Answer

$ \varepsilon = B l v $, $ l = 0.3 \, \text{m} $. $ \varepsilon = 0.6 \times 0.3 \times 1 = 0.18 \, \text{V} $.

Question 3

A rod of length 0.8 m moves at 1.5 m/s in a 0.4 T field perpendicular to its length. What is the induced emf?

Accepted Answer

$ \varepsilon = B l v = 0.4 \times 0.8 \times 1.5 = 0.48 \, \text{V} $.

NEET Physics: Electromagnetic Induction — Practice Set 14

Q1. A metal ring is placed near a solenoid. When an AC current flows through the solenoid, the ring experiences a force. This is primarily due to what?

Q2. A rectangular loop of sides 30 cm and 12 cm moves out of a 0.6 T field at 1 m/s perpendicular to the shorter side. What is the motional emf?

Q3. A rod of length 0.8 m moves at 1.5 m/s in a 0.4 T field perpendicular to its length. What is the induced emf?

Q4. When a bar magnet is moved towards a stationary coil, the induced current flows in a direction that opposes the magnet’s motion. This is an example of which fundamental principle?

Q5. A solenoid of 800 turns/m and area 0.01 m² has \( \mu_r = 1 \). What is its self-inductance? (\( \mu_0 = 4\pi \times 10^{-7} \, \text{H/m} \))

Q6. A solenoid with mutual inductance 0.3 H has a current change of 5 A/s in the primary coil. What is the induced emf in the secondary coil?

Q7. A wheel with 4 spokes of 0.5 m each rotates at 48 rpm in a 0.8 T field. What is the induced emf?

Q8. A rectangular loop of sides 15 cm and 6 cm moves out of a 0.4 T field at 1.5 m/s perpendicular to the shorter side. What is the motional emf?

Q9. A rod rotates at 20 rad/s in a 0.4 T field. If the length from the axis to the tip is 0.5 m, what is the emf induced?

Q10. A conducting rod is moved perpendicular to a uniform magnetic field. The emf induced across its ends depends on which of the following factors?