Question

1. Find the inductance of a coil in which a current increases linearly from 0 to 0.2A in 0.3
Sec, producing a voltage of 15V.
2. A current of 1 A is supplied by a source to an inductor of 1H. Calculate the energy stored
in the inductor. What happens to this energy if the source is short circuited?​

Answer 1

Answer:

In other words, a coil has an inductance, ( L ) of one Henry, ( 1H ) when the current flowing through the coil changes at a rate of one ampere/second, ( A/s ). This change induces a voltage of one volt, ( VL ) in it. Thus the mathematical representation of the rate of change of current through a wound coil per unit time is given as:

current through a coil

Where: di is the change in the current in Amperes and dt is the time taken for this current to change in seconds. Then the voltage induced in a coil, ( VL ) with an inductance of L Henries as a result of this change in current is expressed as:

voltage induced in a coil

Note that the negative sign indicates that voltage induced opposes the change in current through the coil per unit time ( di/dt ).

From the above equation, the inductance of a coil can therefore be presented as