Physics Precision Measurement Report.docx

Physics Precision Measurement Report Abstract: In order to learn and acquire the necessary skills in using a meter rule, vernier calipers, micrometer screw gauge, laboratory balance, ammeter, milli ammeter, micro ammeter, and a travelling microscope, we used these instruments to measure the diameters, the weights and the length of a steel ball, copper wire and a glass rod. Also, in order to learn how to execute the expression of data using significant figures, we will take the measurements obtained, make calculations and obtain new information from these calculations, i.e. the volume and density of various items. Notably, the accuracy and precision of our measurements should increase with the increase of the precision of the instruments used. This would be determined by the calculation of the standard error. Introduction Measurement can simply be described as the process of determining the magnitude of a quantity, let’s say, mass and length, relative to a unit of measurement such as kilogram and meter. Precision measurement on the other hand can be described as the process of evaluating the consistency of measurements by obtaining data using several instruments. Various quantities have different standard units of measurements (SI units). For the purpose of this experiment it would be important to be acquainted with the various quantities and their standard units of measurement. Length The measure of a straight line distance between two separate points along an object. It can also be described as the longest dimension of an object. The SI unit of length is meter (m). The other various sub units include centimeter (cm), millimeter (mm) and micrometer (µm). Mass The measure of the quantity of matter in a body regardless of its volume or any external forces acting upon it. The SI unit of mass if kilogram (kg). The other various sub units include gram (g) and milligram (mg). Electric current The measure of the rate at which charge flows through a conductor. The SI unit of electric current is the Ampere (A). The other various sub units include milliampere (mA) and microampere (µA). NB: It is important to note that the precision and accuracy are in fact not the same thing. The accuracy of a measurement is the extent of closeness of the measurements to the actual value. Conversely, the precision of a measurement is the extent to which repeated measurements show the same results under unchanged conditions. A measurement system can be precise but not accurate,

accurate but not precise, both or neither. An accurate and precise system is said to be ‘valid’. Apparatus/ Equipment Meter rule Vernier calipers Micrometer screw gauge Laboratory balance Ammeter Milli ammeter Micro ammeter Travelling microscope Copper cylinder Steel ball Copper wire Glass rod Procedure In the first part: 1. The various zero errors and reading errors of the various measuring instruments provided (meter rule, vernier calipers, micrometer screw gauge, and laboratory balance) were determined and recorded. 2. The measurements (length, diameter, and mass) of the objects provided were then taken using the appropriate measuring instruments. 3. The results were recorded. In the 2nd part: 1. The various zero errors of the various measuring instruments provided (Ammeter, milliammeter and micro ammeter) were determined and recorded. 2. The measurements (Amperes, mill amperes and microamperes) were determined 3. The results were recorded. Results:

ITEMS Meter rule

Vernie r caliper

Micromet er Screw

Balan ce

MEASURING INSTRUMENTS Ammet Milli Micro er Ammet Ammet er er

Travelling microscope

s

gauge +0.02m m 0.01mm

0.0g

0.02A

0.0mA

-0.1g

0.01A

15.00 g

0.4A

Zero error

0.0cm

0.0cm

Reading error Copper cylinder height Copper cylinder(ex t. D) Copper cylinder(int . D) Steel ball (diameter) Copper wire (length) Copper wire (diameter) Glass rod (diameter) Glass rod (length) Current

0.5m m 5.9cm

0.01c m 5.59c m

1.1cm

1.19c m

11.82mm

_

1.00c m

_

_

2.52c m 5.96c m

25.09mm

_

0.15c m

1.68mm

0.6cm

0.58c m 5.16c m

5.79mm

5.1cm

5.1cm

_

X

Y

Z

+4 µA

0.00

0.00

0.00

+5mA

1.0 µA

0.02 5

0.02 5

0.02 5

260mA

250 µA

4.692 g 0.8g

2.8g

_

Copper cylinder (weight): Manual balance-15.25g Manual balance-4.9g

Steel ball:

Electrical balance-15.00g Electrical balance-4.692g

Copper wire-0.8g Glass rod-2.8g

Volume

Density of the material

Internal volume of copper cylinder External volume of copper cylinder Volume of the steel ball Volume of the glass rod

Calculation of voltage: Instrument From Ammeter From milli Ammeter From voltmeter

Value of Resistance

Density of the material