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MHT CET 2026 (13 May, Shift 2) · Power, Power Factor & Wattless Current

Power, Power Factor & Wattless Current question from MHT CET 2026 (13 May, Shift 2)

Q4MHT CET 2026 · 13 MAY · SHIFT 2Easy

Power, Power Factor & Wattless Current

In an a.c. circuit, if the power factor changes from $0.5$ to $0.25$ then the increase in impedance is

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Answer: (a)

Power factor $\cos\phi = \frac{R}{Z}$ , so $Z = \frac{R}{\cos\phi} \propto \frac{1}{\cos\phi}$ for the same $R$ .
$\frac{Z_2}{Z_1} = \frac{0.5}{0.25} = 2$
So the impedance becomes twice: answer (a) twice.

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