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Match the scenarios in List-I with their corresponding effects on the total power consumed in List-II for electrical appliances having a rated power P₀ at a rated voltage V . Assume the resistance of the appliances remains constant. List-I List-II A. Supply voltage drops by 10 % 1. Total power becomes P₀ 2 B. Supply voltage is halved 2. Total power becomes 2P₀ C. Two identical appliances in series across rated voltag

Options

  1. AA-3, B-1, C-4, D-2
  2. BA-3, B-4, C-2, D-1
  3. CA-4, B-3, C-1, D-2
  4. DA-3, B-4, C-1, D-2

Correct answer

D. A-3, B-4, C-1, D-2

Step-by-step solution

For an appliance of rated power P₀ at rated voltage V , its resistance is R = V^2 P₀ . A. When the supply voltage drops by 10 % , the new voltage is V' = 0.9V . The new power consumed is P' = (0.9V)^2 R = 0.81 V^2 R = 0.81 P₀ . The drop in power is P₀ - 0.81 P₀ = 0.19 P₀ , which is a 19 % decrease. (A 3) B. When the supply voltage is halved, V' = V 2 . The new power is P' = (V/2)^2 R = 1 4 V^2 R = P₀ 4 . (B 4) C. For two identical appliances connected in series, the equivalent resistance is R_ eq = 2R . The total p

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