A potentiometer wire AB is 100 cm long and has a total resistance of 10 ohm. If the galvanometer shows zero deflection at the position C, then find the value (in Ω) of unknown resistance R.

Question

G1 Physics · Accepted Answer

Use the potentiometer balance condition E₁/E₂ = ℓ₁/ℓ₂; when a load is connected, combine it with the cell’s internal resistance relation. Substituting the given values gives 4.