To measure the volume of the material of a hollow cylinder, using a vernier calipers

Theory

Principle of Vernier scale

Vernier scale consists of two types of scales namely main scale and Vernier scale.
Vernier constant (v.c) of a vernier scale = 1 main scale division – 1 vernier scale division
Total reading = main scale reading + (vernier scale reading $\times$ vernier constant)

Suppose, the length of a hollow cylinder is L, internal diameter is D₁and external diameter is D₂.
So, the volume of the hollow cylinder is $V=\frac{\pi}{4}(D_{2}^{2}-D_{1}^{2})L$

Results

1 division of main scale = ______ cm
______ division of vernier scale = _______ division of main scale
1 division of vernier scale = _______ division of main scale
Therefore, vernier constant (VC) = 1 division of main scale – 1 division of vernier scale
= _____ cm – ____ cm = ________ cm

Table for measurement of length, internal diameter and external diameter

Dimensions	No. of Observations	MSR (cm)	VSR	TR = MSR+ (VSR $\times$ VC) (cm)	Average (cm)
Length (L)	1 2 3 4 5
External Diameter(D₂)	1 2 3 4 5
Internal Diameter (D₁)	1 2 3 4 5

Calculations

Volume of the cylinder is
$V=\frac{\pi}{4}(D_{2}^{2}-D_{1}^{2})L$
V = _______ cm³

Precautions and Discussions

1. The cylinder should not be pressed tightly between the jaws of the vernier callipers.
2. Zero error of the instrument should be measures and necessary corrections should be made.
3. The diameter should be measured at different positions and directions.

Viva Questions on vernier callipers

What is vernier caliper?

Vernier caliper is an instrument used for the measurement of length or diameter for spherical objects.

What is vernier constant?

Vernier constant is the difference between the one main scale division and one vernier scale division.

What is vernier caliper least count?

Verner caliper least count is same as that of vernier constant.

Why is vernier caliper better than ruler?

Vernier caliper can measure a length of the order of 0.01 mm or 0.01 cm.
With ruler we can measure the length in the order of 0.1 cm.

What is zero error in vernier caliper?

If the zero of main scale does not coincide with the zero of vernier scale, then an error comes in the measurement. This is known as zero error.

Why the jaws of the slide calipers should be touched with the experimental body lightly?

If it is touched tightly, it can deform the experimental body.

What is the formula for taking measurement?

Total reading = Main scale reading + (Vernier reading $\times$ vernier constant) – zero error