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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 resistance 2 R and 3 R are connected in parallel in an electric circuit. The value of thermal energy developed in 3 R and 2 R will be in the ratio 3 : 2 . In the light of the abo

Options

  1. ABoth statement I and statement II are correct
  2. BBoth statement I and statement II are incorrect
  3. CStatement I is correct but statement II is incorrect
  4. DStatement I is incorrect but statement II is correct.

Correct answer

C. Statement I is correct but statement II is incorrect

Step-by-step solution

Statement 1 - R = 80   Ω When it is cut into 4 equal parts, the resistance of each part will be, R 1 = R 2 = R 3 = R 4 = 20   Ω When these resistances are connected in parallel, R eq   = 20 4 = 5   Ω Hence, the statement I is correct. Statement 2 - When the resistances are connected in parallel, the potential difference between them is same. Therefore, the power consumed can be written as, P = V 2 R ⇒ P 1 P 2 = R 2 R 1 = 2 3 Hence, statement II is incorrect.

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