Question

a step down transformer is used on a 1000V line to deliver 20A at 120V at the secondary coil. if the efficeincy of the transformer is 80% the current drawn from the line is

1) 3A

2) 30A

3) 0.3A

4) 2.4A

Answer 1

Answer:

1) 3A

Explanation:

Efficiency of Transformer (η)= Output/Input

=80/100

=V₂I₂/V₁I₁

I₁=  V₂I₂×100/V₁×80

=120×20×100/1000×80

=3A

Answer 2

Answer:

please refer to the attached image , kudos to u guys :)