Question 258 of 380
A heating element has a resistance of at room temperature. When it is connected to a supply of , a steady current of passes in it and temperature is more than the room temperature. The temperature coefficient of resistance of the heating element is
Show answer and solution
Answer: (B)
Resistance of heating element after temperature increases by (from Ohm's law). The new resistance is related to the temperature coefficient of the heating element as
\Rightarrow \alpha =2\times {10}^{-4}^{\circ}{C}^{-1}
\Rightarrow \alpha =2\times {10}^{-4}^{\circ}{C}^{-1}