PHYSICS LABORATORY REPORT

EXPERIMENT 1.2 : MEASURING LENGTH USING A VERNIER

CALIPER

NAME : NURAINA SAKINA BINTI ZAKRI

NRIC : 951010-11-5076

GROUP : 11SC2

STUDENT ID : 1311171218

DATE : 18th JULY 2013

LECTURER : MR MOHD AZUAN BIN MOHD AZLAN

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INTRODUCTION

Physics is the study of matter and the forces acting on it. In many experiments and

calculation in Physics requires us to measure an assortment of objects using measuring tools

such as the metre rule, vernier callipers and many more. The knowledge and skills to measure

an object accurately is the basic skill needed by someone to carry out an experiment.

A vernier calliper is a measuring tool used to measure the diameter of an object. It

has two scales, one fixed and marked in cm and mm, the other one is moveable (vernier

scale) and is marked in factions of an mm. In this experiment we are going to measure the

diameter of two different spherical objects ie a table tennis ball and a foam ball.

Zero error and parallax error are unavoidable when conducting this experiment.

Through the experiment we will learn how to calculate zero errors and how to take readings

properly to obtain the most accurate measurements.

OBJECTIVE

To measure the diameters of a table tennis ball and a foam ball using a vernier caliper

To identify zero errors and calculate the accurate volume of table tennis ball and foam

ball

APPARATUS/EQUIPMENT

A vernier calliper, a table tennis ball, and a foam ball

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PROCEDURE

1. The zero error on a vernier calliper is checked and noted.

2. Several measurements across different diameters of both balls, table tennis ball and

foam ball, are taken to check if they are perfect spheres.

3. The measurements and reading on the vernier calliper is recorded in a table.

ASSUMPTIONS

Both of the balls are assumed to have perfect spherical shape.

The zero error of the vernier calliper is assumed to be the same for every

measurement

RESULTS

Diameter, d (cm)

Ball Trial 1 Trial 2 Trial 3 Trial 4 Trial 5 Average Error

Table tennis ball 3.760 3.740 3.760 3.760 3.772 3.758 ±0.018

Foam ball 1.846 1.844 1.844 1.851 1.844 1.846 ±0.005

Table 1 show the reading of measurements of table tennis ball and foam ball

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Data Processing

1. Finding Error = Average – Data with biggest difference

2. Finding Percentage uncertainty = Highest data - lowest data × 100%

2

a) Diameter of table tennis ball = (3.758 ±0.018) cm

% uncertainty on the diameter of table tennis ball

= 3.772 - 3.740 × 100%

2

= ±1.6 %

b) Diameter of foam ball = (1.846 ± 0.005) cm

% uncertainty on the diameter of foam ball

= 1.851 – 1.844 × 100%

2

= ±0.35%

3. The volume of the two balls are calculated using the formula

a) Volume of table tennis ball

= 43 π (3.758

2 )3

= 27.7887 cm3

= 27.79 cm3 ( 4 s.f)

b) Volume of foam ball

= 43 π (1.846

2 )3

= 3.2938cm3

= 3.294cm3 ( 4 s.f)

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V=43 πr3

4. The percentage uncertainty and absolute uncertainty on the volume for both balls is

calculated using the formula

Percentage uncertainty = Percentage uncertaintyVolume×100%

Absolute uncertainty = Percentage uncertainty of volume

100×Volume

a) Percentage uncertainty on volume of table tennis ball

= 1.6

27.79×100 %

= ±5.8%

Absolute uncertainty on volume of table tennis ball

= 5.8100

×27.79

= ± 1.6 cm3

b) Percentage uncertainty on volume of foam ball

= o .353.294

×100 %

= ±11%

Absolute uncertainty on volume of foam ball

= 11

100×3.294

= ±0.36 cm3

5. The final expressions on the volume for both objects are

volume

a) Volume of table tennis ball = ( 27.79 ± 1.6 ) cm3

b) Volume of foam ball = ( 3.294 ± 0.36 ) cm3

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DISCUSSION

1. The percentage uncertainty on the diameter of table tennis ball and the foam ball is

±1.6% and ±0.35% respectively. The measurement of diameter of foam ball is more

accurate than that of table tennis ball as its percentage error is lower. The diameter

measurement of the foam ball is accepted as accurate because the percentage error is

less than 1%.

2. The volume for table tennis ball is expressed as ( 27.79 ± 1.6 ) cm3. The volume is

accepted but is inaccurate and needs to be added or subtracted by the error. The

volume for the foam ball is ( 3.294 ± 0.36 ) cm3. The volume is accepted as accurate

because the percentage error is less than 1%. However the volume still needs to be

added or subtracted by the error.

3. The uncertainty in the measurements occurs because of the zero error on the vernier

calliper. . The zero errors are identified and use in the calculations of the volume

CONCLUSION

The measurement of diameters of the table tennis ball and foam ball is accurately measured

using the vernier callipers. The volume of both balls are expressed as ( 27.79 ± 1.6 ) cm3 and

( 3.294 ± 0.36 ) cm3 respectively. The objective is achieved.

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