Question 1
- Define the following:
- mutual inductance;
- self inductance.
- Figure 1 is an inductive circuit.
Calculate the:
- effective inductance;
- inductive reactance of the circuit.
Observation
The expected responses were:
- (i) Mutual Inductance may be defined as that property of inductors through which
emf is induced in one coil as a result of changes in the flux linkage due to changes in current in an adjacent coil. It is a measure of the ability of a coil to oppose changes in current in an adjacent coil.
(ii)Self-inductance may be defined as that property of the coil that determines the emf induced in the coil when magnetic flux linking with it changes with time.
- (i) The equivalent inductance of the 0.6H inductors connected in parallel is
Therefore the equivalent inductance of all 4 inductors is
(ii) The circuit’s effective inductive reactance is
Question 1 required candidates to define the different types of inductance in the first task and calculate effective inductance and inductive reactance of an inductive circuit. The Chief Examiner reported that a good number of the candidates responded well the tasks but the definition of mutual inductance.