# A screw gauge with a pitch of $0.5 \mathrm{~mm}$ and a circular scale with 50 divisions is used to measure the thickness of a thin sheet of Aluminium. Before starting the measurement, it is found that wen the two jaws of the screw gauge are brought in contact, the $45^{\text {th }}$ division coincides with the main scale line and the zero of the main scale is barely visible. What is the thickness of the sheet if the main scale reading is $0.5 \mathrm{~mm}$ and the 25 th division coincides with the main scale line?

Question:

A screw gauge with a pitch of $0.5 \mathrm{~mm}$ and a circular scale with 50 divisions is used to measure the thickness of a thin sheet of Aluminium. Before starting the measurement, it is found that wen the two jaws of the screw gauge are brought in contact, the $45^{\text {th }}$ division coincides with the main scale line and the zero of the main scale is barely visible. What is the thickness of the sheet if the main scale reading is $0.5 \mathrm{~mm}$ and the 25 th division coincides with the main scale line?

1. $0.70 \mathrm{~mm}$

2. $0.50 \mathrm{~mm}$

3. $0.75 \mathrm{~mm}$

4. $0.80 \mathrm{~mm}$

JEE Main Previous Year Single Correct Question of JEE Main from Physics Physical World, Units and Measurements chapter.

JEE Main Previous Year 2016

Correct Option: 4

Solution:

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