JEE Main · 2008 · 27 Apr 2008 · Offline · Units & Measurement

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An experiment is performed to find the refractive index of glass using a travelling microscope. In this experiment distance are measured by

(A)a vernier scale provided on the microscope✓ Correct
(B)a standard laboratory scale
(C)a meter scale provided on the microscope
(D)a screw gauage provided on the microscope

Answer: (A)

Solution

A travelling microscope carries a vernier scale alongside its main scale, and it is this vernier that lets small displacements be read off precisely. In finding the refractive index of glass by the apparent-depth method one records microscope positions for marks seen directly and through the glass, and those positions are measured on the instrument's own vernier scale.

JEE Main · 2008 · 27 Apr 2008 · Offline · Single correct option

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