Question 1: A solenoid is a long coil of wire wrapped in many turns that produces a magnetic field when an electric current flows through it. The magnetic field inside a solenoid is similar to that of a bar magnet. This property is used in various electrical devices.

Answer: A solenoid is a coil of wire that generates a magnetic field when current flows through it, mimicking a bar magnet.

Question 1: Describe how the magnetic field inside a solenoid differs from the field outside the solenoid.

Answer: The magnetic field inside a solenoid is uniform and strong, similar to a bar magnet, while outside it is weaker and less uniform.

Question 2: Explain why increasing the number of turns in a solenoid increases its magnetic field strength.

Answer: More turns increase the magnetic field strength because the magnetic field is proportional to the number of turns per unit length and the current.

Question 1: Calculate the magnetic field inside a solenoid of length 0.5 m, with 200 turns, carrying a current of 3 A. Use the formula B = μ₀ (N/L) I, where μ₀ = 4π × 10⁻⁷ T·m/A.

Answer: B ≈ 15.0 millitesla

Question 2: A solenoid has 1500 turns and is 2 meters long. If the magnetic field inside it is 2.5 × 10⁻³ Tesla when a current of 2 A flows, what is the magnetic permeability of the core material? (μ = B / (μ₀ * (N/L) * I)).

Answer: μ ≈ 1.59 × 10⁻³ H/m

Question 1: Outline the key safety precautions to observe when setting up an experiment involving a solenoid and a power supply.

Answer: Ensure the power supply is turned off before connecting or disconnecting wires, avoid contact with live wires, keep the setup away from water, and do not overload the circuit.

Question 2: Identify at least three variables that should be controlled or kept constant during an experiment measuring the magnetic field of a solenoid.

Answer: Number of turns, length of the solenoid, current supplied, and environmental conditions such as temperature.

Question 1: A solenoid with 300 turns and length 0.75 m carries a current of 4 A. The measured magnetic field inside is 8 × 10⁻³ Tesla. Analysing this data, discuss whether the magnetic permeability of the core is likely to be similar to free space or if it suggests a ferromagnetic core.

Answer: The calculated permeability based on B, N, L, and I suggests a value significantly higher than μ₀, indicating the core is likely ferromagnetic, which increases the magnetic field compared to free space.

Question 1: Describe how solenoids are used in modern technology, providing at least two specific examples.

Answer: Solenoids are used in electric door locks to activate locking mechanisms and in MRI machines to generate strong, controlled magnetic fields for imaging.