Question
An electric wire of length ‘I’ and area of cross-section 
has a resistance R ohms. Another wire of the same material having same length and area of cross-section 4a has a resistance of
- 4R
- R/4
- R/16
- 16R
The correct answer is: R/4
for first wire and R’=
for second wire.
Related Questions to study
The resistance of a wire of uniform diameter d and length L is R. The resistance of another wire of the same material but diameter 2d and length 4L will be
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A 500 gm packet of tea is sold for Rs 80 and a tooth brush costing Rs 11 is given free with it. The shopkeeper thus makes a profit of 15% on it. What did the shopkeeper pay for it?
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0.6395 × 1000 =
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0.6395 × 1000 =
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The remainder of 2100 when divided by 7 is
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A so lid piece of metal in the form of a Cuboid of dimes ions 24 cm x 18 cm x 4 cm is melted down and casted into a cube Find length of each edge of cube.
For such questions, we should know the formulas of volume of different shapes. We have to remember that when any metal piece is melted, it's volume doesn't change. The change is there only in the dimensions of the metal piece.
