This is a sixteenth chapter of the book Physics 12 published by Punjab Curriculum and Textbook Board, Lahore, Pakistan.
Understand and describe time period, frequency, the peak and root mean square values of an alternating current and voltage.
Know and use the relationship for the sinusoidal wave.
Understand the flow of A.C. through resistors, capacitors and inductors.
Understand how phase lags and leads in the circuit.
Apply the knowledge to calculate the reactances of capacitors and inductors.
Describe impedance as vector summation of resistances.
Know and use the formulae ofA.C. power to solve the problems.
Understand the function of resonant circuits.
Appreciate the principle of metal detectors used for security checks.
Describe the three phase A.C. supply.
Become familiar with electromagnetic spectrum (ranging from radio waves to $7$ rays).
Know the production, transmission and reception of electromagnetic waves.