Question

In an L-R series A.C. circuit the potential difference across an inductance and resistance joined in series are respectively $12$$V$ and $16$$V$. Find the total potential difference across the circuit.

• A. $10V$
• B. $20V$
• C. $30V$
• D. $40V$

Answer 1

The correct option is B $20V$

The voltage drop across resistance and Inductor are$V_R$ and $V_L$.

Phase diff between $V_R$ and $V_L$$=\frac{\pi }{2}$

$\therefore V_{resultant}=\sqrt{V_R^2+V_L^2}=\sqrt{{16}^2+{12}^2}=\sqrt{400}=20V$