Significant figures

• Natuurkunde
• Middelbare school
• vwo
• Leerjaar 3

Significante figures and decimals

3Tha

Today

• Recap scientific notation
• Decimals and significant figures
• Questionsrounds

0,83 dm^2= mm^2

1. 83 mm^2
2. 0,0083 mm^2
3. 8300 mm^2
4. 0,000083 mm^2

1 m^3= L

1. 1000 L
2. 10L
3. 0,001 L
4. 0,1 L

Reken om naar mg:
134 ng

Write without prefix and in the scientific notation
12 MN= N

1. 1,2*10^6 N
2. 1,2*10^-6 N
3. 12 000 000 N
4. 1,2*10^7 N

Convert and write in the scientific notation.
0,34 cm= mm

1. 3,4*10^-1 mm
2. 3,4*10^1 mm
3. 3,4*10^0 mm
4. 3,4 mm

write without prefix and in the scientific notation
98 kW= W

Goals

• After totday you know the difference between decimals and significant figures.
• After today you know the 4 rules for significant figures

What is the difference between 24 en 24,0

Decimals

Decimals are all the numbers after the decimal mark

Example

• 5,8        Has 1 decimal
• 5,82      Has 2 decimals
• 5,820   Has 3 decimals

How many decimals has:
72,30780 dm

1. 6
2. 4
3. 7
4. 5

Significant figures

Wat is the length of the rectangle in cm. Give you answer as accurate as possible on the next page.

What is the length of
the rectangle

Significant figures

To be honest, the last figure you noted in your number is an estimate. 

Significant figures

Significante cijfers

 4 rules.

1. Numbers which are not 0 are significant

       (so 1, 2, 3, 4, 5, 6, 7, 8 en 9)

Significante cijfers

4 rules.

1. Numbers which are not 0 are always significant

       (so 1, 2, 3, 4, 5, 6, 7, 8 en 9)

2. zeroes before non-zeroes are not significant numbers. 

Significante cijfers

4 rules.

1. Numbers which are not 0 are always significant

       (so 1, 2, 3, 4, 5, 6, 7, 8 en 9)

2. zeroes before non-zeroes are not significant numbers.

3. zeroes after non-zeroes are significant

Significante cijfers

4 rules.

1. Numbers which are not 0 are always significant

       (so 1, 2, 3, 4, 5, 6, 7, 8 en 9)

2. zeroes before non-zeroes are not significant numbers.

3. zeroes after non-zeroes are significant

4. x10^.... is not significant

1. 10-machten tellen niet mee.

Questionround

How many significant figures??
405,070

1. 3
2. 4
3. 5
4. 6

How many significant figures?
0,000234000

1. 3
2. 6
3. 9
4. 10

How many significant figures
567,3 kg

How many significant figures?
1,0000000003 m

How many significant figures?
-15,3 N

How many significant figures?
5 mensen

how many significant figures?
0,01000000000000054 m/s

How many significant figures?
10,07*10^5 dam

There is a mistake in the last slide, what was it? Who has spotted the mistake? 

Wat heb je vandaag geleerd?

Homework

Exercises paragraph 3.3

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