Question

Distinguish between alternating current and direct current. Which current is preferred for transmission over long distances ?

CBSE Class X Science SA 2 (3 Marks)

Answer 1

Alternating Current : If the current changes direction after equal intervals of time, it is called alternating current. The positive and negative polarities of AC are not fixed.
 
Direct Current : If the current always flows in the same direction, it is called direct current. It can be obtained from a cell or a battery. The positive and negative polarities of DC are fixed for long distance transmission. AC is preferred for long distance transmission. 

Answer 2

Answer:

Alternating Current : If the current changes direction after equal intervals of time, it is called alternating current. The positive and negative polarities of AC are not fixed.

 

Direct Current : If the current always flows in the same direction, it is called direct current. It can be obtained from a cell or a battery. The positive and negative polarities of DC are fixed for long distance transmission. AC is preferred for long distance transmission.