JEE MainPhysicsCurrent ElectricityMCQ+4 / −1
An electric cable of copper has just one wire of radius 9 mm. Its resistance is 14 . If this single copper wire of the cable is replaced by seven identical well insulated copper wires each of radius 3 mm connected in parallel, then the new resistance of the combination will be :
- A9
- B18
- C28
- D126
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