Question

Two circular rings of identical radii and resistance of `36Omega` each are placed in such a way that they cross each others centre `C_1` and `C_2` as shown in figure. Conducting joints are made at intersection point A and B of the rings. An ideal cell of emf 20 volts is connected across AB. The power delivered by cell is:

Answer 1

Correct Answer - 1
The resistance of four sections are shown in figure.
Hence, the equivalent resistance `R` across `AB` is
`(1)/(R ) = (1)/( 24) + (1)/(12) + (1)/(12) + (1)/(24) or R = 4 omega`
Power `= V^(2)//R = 20^(2)//4 = 100 W`