In a Vernier Calipers, 10 divisions of Vernier scale is equal to the 9 divisions of main scale. When both jaws of Vernier calipers touch each other, the zero of the Vernier scale is shifted to the left of zero of the main scale and 4th Vernier scale division exactly coincides with the main scale reading. One main scale division is equal to 1 mm. While measuring diameter of a spherical body, the body is held between two jaws. It is now observed that zero of the Vernier scale lies between 30 and 31 divisions of main scale reading and 6th Vernier scale division exactly coincides with the main scale reading. The diameter of the spherical body will be
- 3.02 cm
- 3.06 cm
- 3.10 cm
- 3.20 cm
The Correct Option is C
Solution and Explanation
The diameter of the spherical body:
\(LC= \frac{1}{10}\; MSD\) \(AS\) \([10 VSD = 9 MSD]\)
= \(0.01\) \(cm\)
\((0.1 – 0.04)\) \(cm\) = \(0.06\) \(cm\) \([ Negative \;Error ]\)
\((3.0 \;cm)\) + \(6(0.01)\) \(cm\) + \(0.06\) \(cm \) \( [Reading ]\)
= \(3.12\) \(cm\)
Which is approximately Closer to \(3.10\) \(cm\)
Hence, the correct option is (C): \(3.10 \; cm\)
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Concepts Used:
Units and Measurement
Unit:
A unit of a physical quantity is an arbitrarily chosen standard that is broadly acknowledged by the society and in terms of which other quantities of similar nature may be measured.
Measurement:
The process of measurement is basically a comparison process. To measure a physical quantity, we have to find out how many times a standard amount of that physical quantity is present in the quantity being measured. The number thus obtained is known as the magnitude and the standard chosen is called the unit of the physical quantity.
Read More: Fundamental and Derived Units of Measurement
System of Units:
- CGS system
- FPS system
- MKS system
- SI units
Types of Units:
Fundamental Units -
The units defined for the fundamental quantities are called fundamental units.
Derived Units -
The units of all other physical quantities which are derived from the fundamental units are called the derived units.