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A metallic wire having resistance of 20 is cut into two equal parts in length. These parts are then connected in parallel. The resistance of this parallel combination is equal to

Options

  1. A20
  2. B10
  3. C5
  4. D15

Correct answer

C. 5

Step-by-step solution

The resistance of a wire depends directly on the length of a wire. Thus if we reduce the length of a wire to half the resistance too will drop to half. Thus now two pieces will have 10 ohm resistance each Thus let equivaent resistance in parallel connection be R _ q : Thus 1 / R _ q =1 / 10+1 / 10R_q=10 / 2=5 ohm

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