Question
What is the difference between a direct current and an alternating current? How many times does AC used in India change direction in one second?
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Answer
Difference between Direct current and an Alternating current:
| | Direct current | Alternating current |
| 1. | The magnitude of direct current is constant and flows in one direction only. | The magnitude of AC changes with time and direction of alternating current reverses periodically. |
| 2. | Direct current cannot be used for large scale supply of electricity for household purpose. | Alternating current is used to run electrical appliances like electric bulb, electric heater, electric iron, refrigerator etc. |
| 3. | The frequency of direct current is zero. | Frequency of alternating current in india is 50Hz. |
Since frequency is 50Hz, so a.c. completes 50 cycles in 1 second. Therefore, it reverses its direction 100 times in one second.
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