7418. The ac system is preferred to de system because-
ac voltages can be easilty changed in magnitude
de motors do not have fine speed control
high voltage ac transmission is less efficient
de voltage cannot be used for domestic appliances
ব্যাখ্যা: Current can be categorized into two types-
1. Alternating current (AC), in which flowing current changes its direction.
2. Direct current (DC), in which the current flows in one directions.