Question

Least count of a vernier callipers is `0.01 cm` When the two jaws of the instrument touch each other the `5th` division of the vernier scale coincide with a main scale division and the zero of the vernier scale lies to the left of the zero of the main scale. Furthermore while measuring the diameter of a sphere, the zero markof the vernier scale lies between `2.4 cm` and `2.5 cm` and the `6th` vernier division coincides with a main scale division. Calculate the diameter of the sphere.

Answer 1

Correct Answer - A::B::C
The instrument has a negative error,
`e = (-5 xx 0.01) cm`
or `e = - 0.05 cm`
Measured reading
= `(2.4 + 6 xx 0.01) = 2.46 cm`
True reading = Measured reading `- e`
= `2.46 - (-0.05)`
= `2.51 cm`
Therefore, diameter of the sphere is `2.51 cm`.