COMEDK · Physics · 23. Alternating Current
Transformer works on \(220 \mathrm{~V}\) and its efficiency is \(80 \%\). If output power is \(8 \mathrm{~kW}\), primary current is approximately
- A \(35 \mathrm{~A}\)
- B \(18 \mathrm{~A}\)
- C \(22 \mathrm{~A}\)
- D \(45 \mathrm{~A}\)
Answer & Solution
Correct Answer
(D) \(45 \mathrm{~A}\)
Step-by-step Solution
Detailed explanation
Given, \(V_{p}=220 \mathrm{~V}, \eta=80 \%=0.8\) \(P_{0}=8 \mathrm{~kW}=8000 \mathrm{~W}\) Efficiency of transformer, \(\eta=\frac{\text { Output power }}{\text { Input power }}\) \(\Rightarrow \quad \eta=\frac{P_{o}}{P_{i}} \Rightarrow 0.8=\frac{8000}{p_{i}}\)…
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