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Given below are two statements: Statement I : A uniform wire of resistance 80 Ω is cut into four equal parts. These parts are now connected in parallel. The equivalent resistance of the combination will be 5 Ω. Statement II : Two resistances 2R and 3R are connected in parallel in an electric circuit. The value of thermal energy developed in 3R and 2R will be in the ratio : 2. In the light of the above statements, choose the most appropriate answer from the option given below. (1) Both statement I and statement II are correct (2) Both statement I and statement II are incorrect (3) Statement I is correct but statement II is incorrect (4) Statement I is incorrect but statement II is correct
- Both statement I and statement II are correct
- Both statement I and statement II are incorrect
- Statement I is correct but statement II is incorrect
- Statement I is incorrect but statement II is correct
Correct answer: Statement I is incorrect but statement II is correct
Solution
Statement I is incorrect because when the wire is cut into four equal parts, the equivalent resistance in parallel is actually 20 Ω, not 5 Ω. Statement II is correct as the thermal energy developed in resistors in parallel is inversely proportional to their resistances, leading to a ratio of 2 for the thermal energy in 3R and 2R.
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