Answer to Question #103739 in Electric Circuits for Masroor Ahmed

Question

How does A/C currents flows in cables connected to source and laod ? Where as net wave of A/C is always equal to zero?

Answer 1

The A/C currents flows changing direction to opposite each 0.02 seconds in countries with 50 Hz mains frequency and each 0.0167 seconds in cables connected to source and load in countries with 60 Hz frequency.

The second question is a bit unclear, but the magnitude of current or voltage is zero (that is, the sine or cosine wave passes through zero value of voltage or current axis) 100 times every single second at 50 Hz or 120 times a second at 60 Hz. The following figure shows that every current or voltage wave passes the point of zero magnitude twice a period:

Source of image: https://www.electronics-tutorials.ws/accircuits/ac-inductance.html