Significant figures

Question 1

Significant figures

Answer 1

indicate the precision of a number/measurement

Question 2

Non-zero numbers

Answer 2

123 has 3 significant figures

Question 3

zeros between non-zero numbers

Answer 3

1002 has 4 significant figures

Question 4

leading zeros

Answer 4

0.00045 has 2 significant figures

Question 5

trailing zeros (if there’s a decimal place then yes if no decimal place then no)

Answer 5

50.0 has 3 significant figures
500 has 1 significant figure

Question 6

exact numbers

Answer 6

counted items such as “3 apples” has an infinite number of significant figures as it is not measured but counted

Question 7

Why significant figures are important

Answer 7

more precise measurements
12m is less accurate than 12.00m

Question 8

Rule for multiplying/dividing

Answer 8

the answer should have the same amount of significant figures as the one with the SMALLEST significant figures.

3.2 x 4.56 =14.6

Question 9

Rule for adding/subtracting

Answer 9

The answer should have the same amount of decimal places as the one with the SMALLEST amount of decimal places.

12.34 + 0.6 =12.9

Question 10

Uncertainties

Answer 10

every measurement has an uncertainty
usually expressed as +/-
shows the range of values within which the true values lie

5.6cm +/- 0.1cm means that the true value could be between 5.5cm or 5.7cm