Why is AC used for power transmission?

AC voltage can be easily stepped up or down using transformers, allowing high-voltage transmission over long distances with minimal energy loss.

What is the frequency of AC in India?

The mains AC supply in India has a frequency of 50 Hz, meaning the current reverses direction 100 times per second.

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Difference Between AC (Alternating Current) and DC (Direct Current)

Electric current comes in two forms based on the direction of electron flow — alternating (AC) and direct (DC).

In short

Alternating current (AC) periodically reverses its direction and is used for power transmission; direct current (DC) flows steadily in one direction and is used in batteries and electronics.

AC (Alternating Current) vs DC (Direct Current) — Comparison Table

Basis	AC (Alternating Current)	DC (Direct Current)
Direction of flow	Reverses periodically	One direction only
Magnitude	Varies (sinusoidal)	Constant
Frequency	50 Hz (India)	Zero
Transformable?	Yes (via transformer)	No
Source	AC generator / mains	Battery, cell, solar
Uses	Power transmission, homes	Electronics, charging

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Frequently Asked Questions — AC (Alternating Current) vs DC (Direct Current)

Why is AC used for power transmission?: AC voltage can be easily stepped up or down using transformers, allowing high-voltage transmission over long distances with minimal energy loss.
What is the frequency of AC in India?: The mains AC supply in India has a frequency of 50 Hz, meaning the current reverses direction 100 times per second.

Difference Between AC (Alternating Current) and DC (Direct Current)

AC (Alternating Current) vs DC (Direct Current) — Comparison Table

Frequently Asked Questions — AC (Alternating Current) vs DC (Direct Current)

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