Physics-
General
Easy
Question
A transformer has an efficiency of 80%. It is connected to a power input of 5kW at 200 V. If the secondary voltage is 250 V, the primary and secondary currents are respectively
- 25 A, 20 A
- 20 A, 16 A
- 25 A, 16 A
- 40 A, 25 A
The correct answer is: 25 A, 16 A
Efficiency 
Input power=5000 W
Input voltage=200 V
primary current, 
Output power 
Output voltage =250 V
Secondary current, 
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