Units & Dimensions
Given below are two statements: one is labelled as Assertion (A) and the other is labelled as Reason (R).
Assertion (A): In Vernier calliper if positive zero error exists, then while taking measurements, the reading taken will be more than the actual reading.
Reason (R): The zero error in Vernier Calliper might have happened due to manufacturing defect or due to rough handling.
In the light of the above statements, choose the correct answer from the options given below:
Show answer and solution
Answer: (b)
- With positive zero error the zero of the vernier is already to the right of the main-scale zero, so every reading is too large; true reading = observed − zero error. (A) is true.
- Zero error can indeed come from manufacturing defects or rough handling, so (R) is true.
- (R) tells the cause of zero error, not why the reading is larger, so it does not explain (A).
- So the answer is (b).