MHT CET · Physics · Alternating Current
If the power factor changes from 0.5 to 0.25 because impedance changes from \(Z_1\) to \(Z_2\) then \(Z_1=x Z_2\). The value of \(x\) is (Resistance remains constant)
- A \(0.1\)
- B \(0.5\)
- C \(0.7\)
- D \(0.4\)
Answer & Solution
Correct Answer
(B) \(0.5\)
Step-by-step Solution
Detailed explanation
\(Z_1 = \frac{R}{\cos\phi_1} = \frac{R}{0.5}\) \(Z_2 = \frac{R}{\cos\phi_2} = \frac{R}{0.25}\)
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