229600 ohm
In the circuit shown in figure the reading of ammeter is the same with both switches open as with both closed. Then find the resistance R. (ammeter is ideal)
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3 Answers
150600Ω
Akash Anand Good work..keep it upUpvote·0· Reply ·2013-07-08 06:05:51
229When both switches are closed the 50-ohm resistor
gets short. With both switches open, we can apply KVL to find the current I in the 100ohm resistor. With the switches closed, the 100ohm resistor and R will be in parallel.The potential difference across them is the same and we can express the current i1 in the 100 ohm in terms of the current I total flowing into the parallel branch whose resistance is R, and the resistance of the 100-ohm resistor. I depends on the equivalent resistance when both switch is closed, so we can express i1 = I in terms of R and solve for R.
- Akash Anand Good work