1/6
Looks like no tags are added yet.
Name | Mastery | Learn | Test | Matching | Spaced |
---|
No study sessions yet.
What are the SI units (physical quantity, unit name, abbreviation)?
Mass → kilogram → kg
Length → metre → m
Time → second → s
Temperature → kelvin → K
Amount of substance → mole → mol
Electric current → ampere → A
Luminous intensity → candela → cd
What are the prefixes and their multiple of unit?
pico (p) → 1 × 10^-12
nano (n) → 1 × 10^-9
micro → 1 × 10^-6
milli (m) → 1 × 10^-3
centi (c) → 1 × 10^-2
deci (d) → 1 × 10^-1
kilo (k) → 1 × 10³
mega (M) → 1 × 10^6
giga (G) → 1 × 10^9
tera (T) → 1 × 10^12
What is meant by ‘random error’?
Can occur when any measurement is being made, and are measurement errors where measurements vary unpredictably
Can occur by external factors affecting the environment, which it may not be possible to control, and also by difficulty in reading a measuring device + deciding the value it shows
Cannot be corrected, but their effect can be mitigated by conducting experiment repeats + reporting mean value calculated
What is meant by the term ‘systematic error’?
Measurement errors in which the measurement differs from true value by a consistent amount each time
Can be caused by way in which measurements are taken, or by faulty measuring device
Possible to correct
What is the difference between ‘accuracy’ and ‘precision’?
Accuracy: measurement in how close the measurement is to the true value. The closer the value, the more accurate the measurement is
Precision: measurement of how close repeated measurements are to each other. The close they are, the more precise the measurement is
What is meant by the term ‘uncertainty’?
Interval in which the true value of the measurement should lie
If there are a range of values taken (eg. when the experiment is repeated several times) then outliers should be discarded and absolute uncertainty is ±(range of measurements / 2)
If there is only one measurement, then the resolution of the measuring equipment can be used instead
% unc = (absolute unc / actual value) x 100