Questions
The resistance of a wire is ‘R’ ohm. If it is melted and stretched to 'n' times its original length, its new resistance will be
detailed solution
Correct option is B
The resistance of a wire of length l and area A and resistivity ρ is given asR=ρlA Given, l'=nlAs the volume of the wire remains constant ∴A'l'=AlA'=All'=Alnl or A'=An∴R'=ρl'A'=ρnlAn=n2ρlA=n2RTalk to our academic expert!
Similar Questions
In an electrical cable there is a single wire of radius 9 mm of copper. Its resistance is 5Ω . 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
799 666 8865
support@infinitylearn.com
6th Floor, NCC Building, Durgamma Cheruvu Road, Vittal Rao Nagar, HITEC City, Hyderabad, Telangana 500081.
free study material
JEE Mock Tests
JEE study guide
JEE Revision Notes
JEE Important Questions
JEE Sample Papers
JEE Previous Year's Papers
NEET previous year’s papers
NEET important questions
NEET sample papers
NEET revision notes
NEET study guide
NEET mock tests
