In an electrical cable there is a single wire of radius $$9$$ mm of copper. Its resistance is The cable is replaced by $$6$$ different insulated copper wires, the radius of each wire is $$3$$ mm. Now the total resistance of the cable will be

Question

In an electrical cable there is a single wire of radius $$9$$ mm of copper. Its resistance is  The cable is replaced by $$6$$ different insulated copper wires, the radius of each wire is $$3$$ mm. Now the total resistance of the cable will be

Infinity Learn · Accepted Answer

Initially : Resistance of given $$cableR=$$ρ lπ ×  $$9$$ ×  $$10$$−$$32$$        …..(i)Finally$$ : Resistance of each insulated copper wire isR'$$=$$ρ lπ ×  $$3$$ ×  $$10$$−$$32$$  $$=$$ $$9RHence$$, equivalent resistance of $$cableReq=R$$'$$6=16$$×ρ lπ ×  $$3$$ ×  $$10$$−$$32$$    $$=$$ $$9$$ $$R6$$….$$(ii)On$$ solving equation $$(i) and (ii) we get $$Req=7.5$$  Ω

In an electrical cable there is a single wire of radius 9 mm of copper. Its resistance is The cable is replaced by 6 different insulated copper wires, the radius of each wire is 3 mm. Now the total resistance of the cable will be

Remember concepts with our Masterclasses.

Ready to Test Your Skills?

free study material