Screw Gauge Reading Calculation — the NEET Physics formula with its derivation, variables, validity constraints and worked solver.
Screw Gauge Reading Calculation Used for determining the true linear dimension of an object by measuring the displacement using a screw gauge, accounting for zero error. Determine the Main Scale Reading (MSR) by reading the main scale directly. Count the number of complete rotations of the circular scale (n CSD). Calculate the total measured reading by summing MSR and (n CSD LC screw). Apply the zero correction (C0) to find the true reading: x true = Total Reading + C0. n CSD must be a non-negative integer. The zero correction (C0) must be determined separately and applied at the end. Forgetting to include the zero correction (C0), leading to systematic error. Confusing the least count (LC screw) with the pitch of the screw gauge. Assuming the reading is simply the value shown on the main scale.