AC Current vs DC Current — Difference (with Table & FAQs)
AC Current vs DC Current compared side by side — a 5-row comparison table, 4 key points and 3 exam FAQs. Class 12 Physics, free and no sign-up.
TL;DR: AC Current vs DC Current compared side by side — a 5-row comparison table, 4 key points and 3 exam FAQs. Class 12 Physics, free and no sign-up.
Written & reviewed by the Syllab.in Academic Team (CBSE/NCERT subject experts) · Updated
The main difference between AC Current and DC Current: Alternating current and direct current are the two main forms of electrical current used in homes and industries across India. Mastering their differences
AC Current vs DC Current — Comparison Table
| Basis | AC Current | DC Current |
|---|---|---|
| Direction of flow | Changes direction periodically | Flows in one direction only |
| Source | Alternator, power stations | Battery, cell, solar panel |
| Frequency in India | 50 Hz | 0 Hz (constant) |
| Efficiency | Can be transmitted over long distances | Loses energy over long distances |
| Applications | Home appliances, factories, streets lights | Electronics, mobile phones, flashlights |
Key Points
- AC current reverses direction periodically; DC current flows in one direction
- India uses 50 Hz AC current for domestic and industrial supply
- AC can be stepped up or down using transformers, making it efficient for transmission
- DC is preferred for electronic circuits but batteries discharge over time
Frequently Asked Questions
What is the difference between AC and DC?
In direct current the charge flows steadily in one direction only. In alternating current the direction of flow reverses periodically, so the current rises, falls, reverses and repeats.
Which one comes out of a household socket in India?
Household supply is alternating current. Batteries, by contrast, supply direct current, which is why devices that run on batteries need an adapter to work from a wall socket.
Why is AC used for transmitting electricity over long distances?
Because its voltage can be raised and lowered easily using a transformer. Transmitting at high voltage reduces the current for the same power, which cuts the energy wasted as heat in the wires; the voltage is then stepped back down near the consumer.