The figure below shows a circuit of four resistors that are
The figure below shows a circuit of four resistors that are connected to a larger circuit. The graph below the circuit shows the electric potential v(x) as a function of x along the lower branch of the circuit, through resistor 4; the potential Va is 12.0 v. the graph above the circuit shows the electric potential v(x) versus position x along the upper branch of the circuit through resistors 1, 2, and 3; the potential differences are delta VB = 2.00 V and delta Vc = 5.00 V. Resistor 3 has resistance of 200 ohms.
1. What is the resistance of resistor 1?
2. What is the resistance of resistor 2?
Solution
The Potential across R1 ,R2 and R3 is 12 Volts.So Voltage across Resistor 3 is
V3=12-5-2 =5 Volts
Current flowing in the upper branch
I=V3/R3 = 5/200 =0.025 A
1.
So resistance 1 is
R1 =VB/I =2/0.025
R1=80 ohms
2.
So resistance 2 is
R2=VC/I =5/0.025
R2=200 ohms

