Question

14. A step down transformer converts a voltage of 2000V into 220Vin the transmission line. Number of turns in the primary is 5000. Efficiency of the transformer is 90% and output power is 8kW. (i) Calculate the number of turns in the secondary (ii) input power. [2]​

Answer 1

Answer:

Efficiency of a transformer is defined as the ratio of output power to the input power. A transformer which decreases the AC voltage is called a step down transformer. Transformer is an essentially an AC device. It cannot work on DC. A transformer changes AC voltage/currents. Efficiency of transformer is given by

η=

input power

output power

=

E

p

I

p

E

s

I

s

Here, P

output

=8 kW,η=90%

P

input

=

90

8×100

=

9

80

kW

=8.89 kW

Answer 2

Answer:

its only be known as 90% not that much long answer