Menu Close

Problem 2: A carbon electrode has a resistance of 0.125 at 20oC.The temperature coefficient of carbon is -0.0005 at 20oC. What will be the resistance of electrode at 85oC?


Given                    R1 = 0.125      t1 = 20oC              

                          α = -0.0005 K-1                   t2= 85oC

Required              R2 =?

Strategy:            Resistance of a substance depends upon the temperature. The relation is given by

 ∆t is the change in the temperature. Here in this case, ∆t = 85 – 20 = 65oC. Therefore, use the above formula to find the resistance of carbon at 85oC.

Thus there is a slight decrease in the resistance of carbon.


  1. Pingback:numerical-problems-electricity-chapter-2-physics-12

  2. Pingback:numerical-problem-1-current-electricity-chapter-2-physics-12 – msa

  3. Pingback:numerical-problem-3-current-electricity-physics-12 – msa

Leave a Reply

Your email address will not be published. Required fields are marked *