Question

The measurement of an unknown resistance R is to be carried out using Wheatstones bridge (see Fig. 3.25 of NCERT Book). Two students perform an experiment in two ways. The first students takes R₂ = 10Ω and R₁ = 5Ω. The other student takes R₂ = 1000Ω and R₁ = 500Ω. In the standard arm, both take R₃ = 5Ω. Both find R=R₂/R₁ R₃=10 Ω within errors. 

(a) The errors of measurement of the two students are the same. 

(b) Errors of measurement do depend on the accuracy with which R₂ and R₁ can be measured. 

(c) If the student uses large values of R₂ and R₁, the currents through the arms will be feeble. This will make determination of null point accurately more difficult. 

(d) Wheatstone bridge is a very accurate instrument and has no errors of measurement.

Answer 1

(b), (c)

(b) Errors of measurement do depend on the accuracy with which R₂ and R₁can be measured. 

(c) If the student uses large values of R₂ and R₁, the currents through the arms will be feeble. This will make determination of null point accurately more difficult.