Question

If an ideal battery of e.m.f. 10 V is connected with external resistance 9Ω and a wire of length 10 m and resistance 1Ω in series as shown in figure, then calculate potential gradient for potentiometric wire.

• A. 1 V/m
• B. 0.1 V/m
• C. .01 V/m
• D. 10 V/m

Answer 1

Answer: (B)

0.1 V/m

Answer 2

Current through wire = $\frac{10}{9 + 1}$ = 1A

∴ Potential drop across wire = 1 × 1 = 1 volt

∴ φ = $\frac{1}{10}$ = 0.1 volt/m