First slide

Temperature dependence

Question

Two resistances R₁ and R₂ are made of different materials. The temperature coefficient of the material of R₁ is a and of the material of R₂ is $- β$ . The resistance of the series combination of R₁ and R₂ will not change with temperature, if R₁/R₂ equals

Moderate

A

$\frac{α}{β}$
B

$\frac{α + β}{α - β}$
C

$\frac{α^{2} + β^{2}}{α β}$
D

$\frac{β}{α}$

Solution

$\begin{array}{l} R_{1} + R_{2} = R_{1} (1 + αt) + R_{2} (1 - βt) \\ \Rightarrow R_{1} + R_{2} = R_{1} + R_{2} + R_{1} αt - R_{2} βt \Rightarrow \frac{R_{1}}{R_{2}} = \frac{β}{α} \end{array}$

Get Instant Solutions

When in doubt download our app. Now available Google Play Store- Doubts App

Recieve an sms with download link

Doubts App

OR

SCAN ME

Doubts App

Doubts App