Question Detail
Question
Four 20-Ω resistors are connected in parallel and the combination is connected to a 20-V emf device. The current in the device is:
Correct Answer
Option C is the correct answer.
Detailed Explanation
When four identical resistors are connected in parallel, the equivalent resistance (R_eq) is the resistance of one resistor divided by the number of resistors. So, R_eq = 20 Ω / 4 = 5 Ω.According to Ohm's Law, the current (I) in the device is given by I = V / R_eq, where V is the emf. Given V = 20 V and R_eq = 5 Ω, the current I = 20 V / 5 Ω = 4.0 A.
Hint
First, calculate the equivalent resistance for parallel resistors. Then, use Ohm's law.