Resistance

The resistance of a metal at temperature can be related to its resistance at a reference temperature (300 K in this case) using the formula: . Here, is the temperature coefficient of resistance.

1. We are given that the resistance at temperature , , is 20% more than . Therefore, we can express as: .

2. Substitute the expression for into the resistance formula: .

3. Simplify and solve for :

• Cancel from both sides: .
• Rearrange to find: .
• Solve for :
  .
• Thus,

Therefore, the temperature at which the resistance becomes 20% more than its resistance at 300 K is 1300 K.