Alternating Current

Question 1

Peak value/amplitude

Answer 1

The maximum absolute value of the alternating current or voltage in either direction of zero value in a periodic cycle.

Question 2

Period of AC

Answer 2

The period of an AC source refers to the time taken to complete one cycle.

Question 3

Frequency of AC

Answer 3

The frequency of an AC source refers to the number of complete cycles per unit time.

Question 4

Root-mean-square of an AC*

Answer 4

Root-mean-square current of C is the value of the STEADY DIRECT CURRENT which would DISSIPATE HEAT at the SAME AVERAGE RATE in a given resistor

Question 5

Hysteresis

Answer 5

The magnetisation of the core in a transformer is repeatedly reversed by the alternating magnetic field. The energy required to magnetise the core is not entirely recovered during demagnetisation. So we use a soft iron core which has low hysteresis and can be easily magnetised and demagnetised.