Unit 1: introductory concepts Flashcards
accuracy
how close a set of measurements are to the known value
precision
how close a set of measurements are to each other
How many significant figures are in this number?
5000
1
The trailing zeros don’t count.
Rewriting 5 kg as 5000 g doesn’t change the number of sig figs.
Look at it in scientific notation: 5 x 103
How many significant figures are in this number?
0.0037
2
The zeros before the “37” don’t count.
Rewriting 3.7 g as 0.0037 kg doesn’t change the number of sig figs.
Look at it in scientific notation: 3.7 x 10-3
How many significant figures are in this number?
0.104
3
The zero in front doesn’t count.
Look at it in scientific notation: 1.04 x 10-1
How many significant figures are in this number?
607
3
Look at it in scientific notation: 6.07 x 102
How many significant figures are in this number?
9.040
4
The trailing zeros are significant if they are decimal places.
It is the same in scientific notation: 9.040
Low precision and low accuracy
accurate but not precise
precise but not accurate
accurate and precise
error bars
show the amount + / - that the data point could be off by
Tell you about precision
callibrating an instrument
helps with accuracy
