1.

Expresss Joule's law of heating mathematically. What is the resistance of 12m wire having radius 2 times 10^-4m and resistivity 3.14 times 10^-8 Omega .m?

Answer»

Solution :For mathematical expression of Joule.s law of heating, see point Number 29 under the heading " Chapter At a GLANCE"
As PER Question length of WIRE L=12m, radius `r=2 TIMES 10^-4 m` and resistivity `p=3.14 times 10^-8 Omega .m`
`THEREFORE` Resistance of given wire `R=(rho L)/A=(rho L)/(pi r^2)= (3.14 times 10^-8 times 12)/(3.14 times (2 times 10^-4)^2)=3 Omega`


Discussion

No Comment Found

Related InterviewSolutions