AP EAMCET202120 Aug 2021Morning ShiftPhysicsAlternating CurrentActual
A 20 V AC is applied to a circuit consisting of a resistor and a coil with negligible resistance. If the voltage across the resistor is 12 V , the voltage across the coil is
Options
- A16   V
- B10   V
- C8   V
- D6   V
Correct answer
A. 16   V
Step-by-step solution
As the resistance and coil or inductor are in series with power supply, therefore the voltage in the inductor will lead the voltage in resistor by 90 ° ,   the phasor diagram is, So, V net = 20   V = V R 2 + V I 2   and given that V R = 12   V Therefore, V I = 20 2 - 12 2 = 16   V Hence, voltage across the coil is, 16   V