Question

$A\, 2\,V$ battery, a $15\, \Omega$ resistor and a potentiometer of $100\, cm$ length, all are connected in series. If the resistance of potentiometer wire is $5\, \Omega$ , then the potential gradient of the potentiometer wire is

• A. $0.005\, V/cm$
• B. $0.05\, V/cm$
• C. $0.02\, V/cm$
• D. $0.002\, V/cm$

Answer 1

Answer: (A)

$0.005\, V/cm$

Answer 2

Potential gradient $\frac{dv}{dx}=\frac{e}{\left(R+R_{h}+r\right)}. \frac{R}{L}$
$=\frac{2}{\left(15+5+0\right)}\times\frac{5}{1}$
$=0.5\,V / m$
$=0.005\,V /cm$