Share
A generator is connected to a resistor and a 0.049-H inductor in series. The rms voltage across the generator is 7.9 V. When the generator f
Question
A generator is connected to a resistor and a 0.049-H inductor in series. The rms voltage across the generator is 7.9 V. When the generator frequency is set to 100 Hz, the rms voltage across the inductor is 2.8 V. Determine the resistance of the resistor in this circuit
in progress
0
Physics
4 years
2021-08-12T06:24:46+00:00
2021-08-12T06:24:46+00:00 1 Answers
14 views
0
Answers ( )
Answer:
56.04 ohms
Explanation:
The voltage across the inductor VL = IXL
I is the total current flowing in the circuit and XL is the inductive reactance.
First we need to get the current flowing in the circuit.
From the expression above;
I = VL/XL
Since XL = 2πfL
I = VL/ 2πfL
Given VL = 2.8V, frequancy f = 100Hz and inductance L = 0.049-H
I = 2.8/2π*100*0.049
I = 2.8/30.79
I = 0.091A
Also;
Vrms = VL + VR
VR is the voltage across the resistor.
VR = Vrms – VL
VR = 7.9 – 2.8
VR = 5.1V
Then we can calculate the resistance of the resistor
According to ohms law VR = IR
Since the inductance and resistance ar connected in series, the same current will flow through them.
R = VR/I
R = 5.1/0.091
R = 56.04 ohms
Hence the resistance of the resistor in this circuit is 56.04 ohms