NTA Abhyas JEE Main2020PhysicsCurrent ElectricityPractice
Two circular rings of identical radii and resistance 36 Ω are placed as shown in the figure. Conducting joints are made at points A and B and a cell of emf 20 V is connected between these two points. What is the power (in W ) delivered by the cell? [ C 1 and C 2 are the centres of the two rings]
Correct answer
100
Step-by-step solution
From the figure. AC 1 = AC 2 = C 1 C 2 = radius ∴ ∠ AC 1 B = 1 2 0 0 In between A and B, 4 resistances are in parallel Hence the resistance of four sections are in parallel Hence equivalent resistance R across AB is 1 R = 1 2 4 + 1 1 2 + 1 1 2 + 1 2 4 or R = 4 Ω ∴ Power V 2 R = 2 0 2 4 = 1 0 0 watt