In the circuit shown in the figure, neglecting the source resistance, the voltmeter and ammeter readings…

In the circuit shown in the figure, neglecting the source resistance, the voltmeter and ammeter readings respectively are
  1. $0 \mathrm{~V}, 8 \mathrm{~A}$
  2. $150 \mathrm{~V}, 3 \mathrm{~A}$
  3. $150 \mathrm{~V}, 6 \mathrm{~A}$
  4. $0 \mathrm{~V}, 3 \mathrm{~A}$

Solution

$\mathrm{R}=30 \Omega, \mathrm{X}_{\mathrm{L}}=25 \Omega, \mathrm{X}_{\mathrm{C}}=25 \Omega$ $\therefore \quad \mathrm{Z}=\sqrt{\left(\mathrm{X}_{\mathrm{L}}-\mathrm{X}_{\mathrm{C}}\right)^2+\mathrm{R}^2}=30 \Omega$ $\therefore$ Reading of ammeter, $I_{\mathrm{rms}}=\frac{\mathrm{V}_{\mathrm{rms}}}{\mathrm{Z}}=\frac{240}{30}=8 \mathrm{~A}$ Reading of voltmeter, $\mathrm{V}=\mathrm{I}_{\mathrm{rms}} \sqrt{\left(\mathrm{X}_{\mathrm{L}}-\mathrm{X}_{\mathrm{C}}\right)^2}=8 \sqrt{(25-25)^2}=0\mathrm{V}$

Asked in: AP EAMCET 2024 (22 May Shift 2)

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