The temperature coefficient of resistance of copper is `42.5times10^(-4^@)C^-1`. The resistance of a coll of copper at `30^@C` is `8Omega`.What is the resistance at `100^@C`?

Explanation

`R=R_0(1+at)=R_0a(1/alpha+t)`
`At 30^@C,R_(30)=R_0alpha(1/alpha+t)`
`At 100^@C,R_(100)=R_0alpha(1/alpha+100)`
`So,R_(100)/R_(30)=(1/alpha+100)/(1/alpha+30)`
Now, `1/alpha=1/(42.5times10^-4)=10000/42.5=235.3`
So,`R_(100)=R_30times(235.5+100)/(235.3+30)=8times335.3/265.3=10.1Omega`