In the figure below, the voltage across the 18 ohm resistor

Home » Network Theory » Network Elements and the Concept of Circuit » Question

In the figure below, the voltage across the 18 ohm resistor is 90 volts. What is the total voltage across the combined circuit at terminal E and F?

1. 125 V
2. 16 V
3. 24 V
4. 40 V

Correct Option: A

In the given circuit voltage across 18 Ω is 90 V: so, I across 18 Ω will be

I =	90	= 5 amp.
	18

Voltage drop across AB = 5. 3 || 6 = 5 × 2 = 10 V
Voltage drop across AC = 90 + 10 = 100 V

Current in 5 Ω resistor =	100	= 20 amp.
	5

so, Current flowing through 1 Ω resistor = 20 + 5 = 25 amp.
Voltage drop across 1 Ω = 25 × 1 = 25 V
so, voltage drop across the terminal E and F
= 25 + 100 = 125 V