All Problems

Electric Current

Problem 3.179

Fig. 3.43 illustrates a potentiometric circuit by means of which we can vary a voltage \(V\) applied to a certain device possessing a resistance \(R .\) The potentiometer has a length \(l\) and a resistance \(R_{0},\) and voltage \(V_{0}\) is applied to its terminals. Find the voltage \(V\) fed to the device as a function of distance \(x\). Analyse separately the case \(R \gg R_{0}\).

Reveal Answer
 3.179. V=V0Rx/[Rl+R0(l−x)x/l]; for R≫R0V≈≈V0x/l\begin{aligned} &\text { 3.179. } V=V_{0} R x /\left[R l+R_{0}(l-x) x / l\right] ; \quad \text { for } \quad R \gg R_{0} \quad V \approx\\ &\approx V_{0} x / l \end{aligned}
Prev
Next