Electronics - Transformers - Discussion
Discussion Forum : Transformers - General Questions (Q.No. 2)
2.
A transformer is plugged into a 120 V rms source and has a primary current of 300 mA rms. The secondary is providing 18 V across a 10 
load. What is the efficiency of the transformer?
load. What is the efficiency of the transformer?Discussion:
14 comments Page 2 of 2.
Ramesh said:
1 decade ago
Input watt 120*.3(V*I) = 36.
Output watt :
So I = V/R(18/10) = 1.8.
18*1.8 = 32.4 watt.
Eff = output/input.
32.4/36 = 0.90.
So the answer is B.
Output watt :
So I = V/R(18/10) = 1.8.
18*1.8 = 32.4 watt.
Eff = output/input.
32.4/36 = 0.90.
So the answer is B.
Viyoo said:
1 decade ago
Pin = 120*0.3=36W.
Pout = 18*18/10=32.4.
efficiency = Pin/Pout.
= (32.4/36)*100.
= 90%.
Pout = 18*18/10=32.4.
efficiency = Pin/Pout.
= (32.4/36)*100.
= 90%.
V seenivasan said:
9 years ago
Fantastic explanation, Thank you all.
Ammu said:
9 years ago
Superb and helpful explanations.
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