**1. What is Faraday’s law of electromagnetic induction?**

**Answer:** Faraday’s law states that the induced electromotive force (emf) in any closed circuit is directly proportional to the rate of change of magnetic flux through the circuit.

**2. Explain induced emf and current in electromagnetic induction.**

**Answer:** Induced emf is the electromotive force generated in a conductor when it experiences a change in magnetic flux. According to Lenz’s law, the induced current flows in such a direction as to oppose the change that produced it.

**3. What is Lenz’s Law?**

**Answer:** Lenz’s Law states that the direction of the induced current in a conductor will be such that it opposes the change that caused it. This law ensures that energy is conserved in electromagnetic systems.

**4. Discuss eddy currents in electromagnetic induction.**

**Answer:** Eddy currents are swirling currents induced in conductors when subjected to a changing magnetic field. They circulate within the conductor, generating heat and causing energy losses in electrical devices.

**5. Define self and mutual inductance.**

**Answer:** Self-inductance is the ability of a circuit to induce an electromotive force (emf) in itself when the current through it changes. Mutual inductance refers to the ability of one circuit to induce an emf in an adjacent circuit when the current in the first circuit changes.

**6. What are alternating currents (AC)?**

**Answer:** Alternating currents are electrical currents that periodically change direction and magnitude over time. They are commonly used in household electricity and power transmission.

**7. Explain the peak and RMS value of alternating current/voltage.**

**Answer:** The peak value of alternating current/voltage is the maximum value reached during one cycle of alternating current/voltage. The RMS (Root Mean Square) value is the effective value of the alternating current/voltage, equivalent to the direct current/voltage that would produce the same amount of power dissipation in a resistive load.

**8. Discuss reactance and impedance in alternating current circuits.**

**Answer:** Reactance is the opposition offered by an inductor or capacitor to the flow of alternating current, measured in ohms. Impedance is the total opposition to the flow of alternating current in a circuit, comprising resistance, inductive reactance, and capacitive reactance.

**9. Explain the LCR series circuit and resonance.**

**Answer:** An LCR series circuit contains a combination of inductance (L), capacitance (C), and resistance (R) connected in series. Resonance occurs when the capacitive reactance equals the inductive reactance, resulting in maximum current flow and minimum impedance in the circuit.

**10. What is the power in AC circuits?**

**Answer:** In AC circuits, power is the product of voltage and current, taking into account the phase difference between them. It can be calculated using various methods such as using the RMS values of voltage and current.

**11. Define wattless current in AC circuits.**

**Answer:** Wattless current, also known as reactive current, is the component of current in an AC circuit that is out of phase with the voltage. It represents the flow of reactive power, which oscillates between the source and load but does not contribute to real power consumption.

**12. Discuss the working principle of an AC generator.**

**Answer:** An AC generator, also known as an alternator, works on the principle of electromagnetic induction. It consists of a rotating coil (armature) placed within a magnetic field. As the coil rotates, the magnetic flux through it changes, inducing an emf and generating alternating current.

**13. Explain the functioning of a transformer.**

**Answer:** A transformer consists of two coils, primary and secondary, coupled by a magnetic core. Alternating current in the primary coil produces a changing magnetic flux, inducing an emf in the secondary coil through electromagnetic induction. This allows for the transformation of voltage and current levels between the primary and secondary circuits.

**14. How does a step-up transformer differ from a step-down transformer?**

**Answer:** A step-up transformer increases the voltage from the primary to the secondary coil, while a step-down transformer decreases the voltage. This is achieved by having a greater number of turns in the secondary coil for a step-up transformer and a smaller number of turns for a step-down transformer.

**15. What is the purpose of the magnetic core in a transformer?**

**Answer:** The magnetic core in a transformer provides a path for the magnetic flux generated by the primary coil to link with the secondary coil. It enhances the efficiency of electromagnetic induction and reduces energy losses due to eddy currents and hysteresis.

**16. Discuss the importance of laminating the core in transformers.**

**Answer:** Laminating the core involves stacking thin sheets of ferromagnetic material to reduce eddy current losses. This improves the efficiency and performance of transformers by minimizing energy losses in the core material.

**17. Explain how transformers are used in power transmission.**

**Answer:** Transformers are used in power transmission to step up the voltage of electrical energy generated at power plants for efficient long-distance transmission over power lines. At the destination, step-down transformers lower the voltage to safe levels for distribution and use.

**18. What is the significance of resonance in AC circuits?**

**Answer:** Resonance in AC circuits results in maximum current flow and minimum impedance, making it useful in various applications such as tuning circuits, filtering signals, and enhancing power transfer efficiency in electrical systems.

**19. How do transformers contribute to energy conservation in power distribution?**

**Answer:** Transformers help conserve energy in power distribution by allowing for efficient voltage transformation, reducing energy losses during transmission, and enabling the use of higher voltages for long-distance transmission, which reduces the amount of current required.

**20. Discuss the role of impedance matching in electrical systems.**

**Answer:** Impedance matching involves designing electrical systems to ensure that the impedance of the load matches that of the source or transmission line. This maximizes power transfer efficiency, minimizes reflections, and prevents damage to equipment in the system.