Potential Gradient Definition — the NEET Physics formula with its derivation, variables, validity constraints and worked solver.
Potential Gradient Definition This specific formula applies to calculating an unknown resistance or ratio using the principle of the meter bridge circuit. The meter bridge principle relies on balancing the potential difference across the unknown resistance ( R x ) and the known resistance ( R ). The ratio of resistances is set equal to the ratio of the corresponding lengths: R x R = l 100-l . Rearranging the formula to solve for the unknown resistance R x (represented here as X ). The final derived relationship is X = R ( 100 - l l ) . 0 < l < 100 The circuit must be balanced for the measurement to be valid. Confusing the ratio of resistances with the ratio of potentials. Forgetting to account for the total length (100 cm) when setting up the ratio. Assuming the potential gradient is constant regardless of the circuit setup.