1 Working as a Physicist Flashcards
Pico(p)
x10^-12
Nano(n)
x10^-9
Micro(u)
x10^-6
Milli(m)
x10^-3
Kilo(K)
x10^3
Mega(M)
x10^6
Giga(G)
x10^9
Tera(T)
x10^12
What are the all SI units?
- distance(m)
- mass(kg)
- time(s)
- current(A)
- temp(K)
- amount of substance(mol)
- luminous intensity(cd)
What is the independent variable?
The thing you change
What is the dependent variable?
The thing you measure
What is the absolute uncertainty?
The total uncertainty for a measurement
What is the percentage uncertainty?
The uncertainty given as a percentage of the measurement
How can the absolute uncertainty be found?
1/2 the resolution of the measurement
If you add or subtract uncertainties what should you do?
Add the absolute uncertainties
If you have to multiply or divide uncertainties what should you do?
Add the percentage uncertainties
If you have to raise an uncertainty to the power what should you do?
Multiply the percentage uncertainty by the power
How can uncertainties be shown on a graph?
By using error bars
What does valid mean?
You are measuring what you’re supposed to be measuring
What does precise mean?
There is a small range in your repeated data
What does repeatable mean?
You can repeat the experiment and get the same results
What does reproducible mean?
The same result must be reached by different experimenters, using different equipment and methods
What does accurate mean?
A result that is really close to the true value
What is a systematic error?
An error that is the same every time so affects the accuracy but not the precision
What are random errors?
They are errors that occur naturally ie human error
How can random errors be reduced?
Use apparatus with better resolution
Do more repeats
