Chapter 1: Measurement Flashcards
What is a physical quantity? Consists?
A quantity that can be measured. It consists of a numerical magnitude and a unit
What is a base quantity? Examples?
Set of independent physical quantities
Length, metre, m Mass, kilogram, kg Time, second, s Temperature, kelvin, K Electric current, ampere, A Amount of substance, mole, mol
What is a derived quantity?
Given by the multiplication or division of two or more base quantities
Prefixes
10^9 giga G 10^6 mega M 10^3 kilo k 10^-1 deci d 10^-2 centi c 10^-3 milli m 10^-6 micro weird u 10^-9 nano n
What are the measuring instruments?
- Tape measure
- Metre rule
- Vernier calipers
- Micrometer screw gauge
Random error
Repeat the measurement and take the average value of the measurements
Zero error
The 0cm mark may not exactly be at the end of the rule
Parallax error
Position your eyes such than your line of sight is perpendicular to the rule
Tape measure
Precision: 0.1cm
Measuring range: Several metres
Metre rule
Precision: 0.1cm
Measuring range: Several cm to 1m
Vernier calipers
Precision: 0.01cm
Measuring range: 1cm to 15cm
Micrometer screw gauge
Precision: 0.001cm
Measuring range: Less the 2.5cm
What is one oscillation?
Each complete to-and-fro motion
What is period?
Time taken for one complete oscillation
What is pendulum?
A more precise way to measure a fixed interval of time
