Question

A 2 volt battery, a 15 Ω resistor and a potentiometer of 100 cm length, all are connected in series. If the resistance of potentiometer wire is 5 Ω, 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. 0.2 V/cm

Answer 1

Answer: (A)

0.005 V/cm

Answer 2

By using $x = \frac{e}{(R + R_{h} + r)}.\frac{R}{L}$

⇒ $x = \frac{2}{(5 + 15 + 0)} \times \frac{5}{1} = 0.5V ⥂ / ⥂ m = 0.005V ⥂ / ⥂ cm$