Triple Beam Balance Lesson

Scientific Information

• Observation vs Inference

  • Observation → a fact that is determined by using your 5 senses

    • Example: A dog measures 14 inches tall

    • You can never observe feelings - you can only infer them

  • Inference → what you think based on your observations - it can also be a prediction about the future

    • Example: It is going to rain

  • Scientific Method - An organized way of solving a problem

    • There are about 7 Steps: 

1. Problem - usually in the form of a question that you want to solve

2. Hypothesis - an educated guess based on research and knowledge

3. Design Experiment 

4. Conduct an Experiment - make and record your observations!

5. Analyze Results - use graphs and charts

6. Conclusion - what did you determine?

7. Share your results

Open Ended

Make an observation about the globe.

Open Ended

Make an inference about the globe.

Add each number the beam is pointing to.

50 + 100 + 5 = 155 grams

How do I measure mass?

• The measure of matter inside an object (M&M → Mass & Matter)

  • Measured using a triple beam balance - Usually in grams (g)

Mass

Measurement

Multiple Choice

What is the mass on this triple beam?

• 221.5g

• 222.5g

• 20g

Multiple Choice

What is the mass of this object?

• 328 grams

• 300.2.8 grams

• 333 grams

• 302.8 grams

Volume

The measure of the amount of space an object takes up 

• Measured using a graduated cylinder - Usually in (mL)

  • In a regular solid, can be measured as volume = length x width x height

  • To find the volume of an irregular shaped object you must use the dunk method!

​Volume of a Regular Solid

​The Dunk Method

Volume = 78 mL - 58 mL 

Volume = 20 mL

Multiple Choice

What is volume?

• how heavy it is

• how much space it takes up

• how much matter is in the object

• the shape of the object

Multiple Choice

What units is volume measured in?

• grams

• degrees

• milliliters or cm3

• pounds

Multiple Choice

Which equation would help you find the volume?

• 5-4=1 mL

• 5.6-4.8=0.8 mL

• 4-5=1 mL

• 5+4=9 mL

Multiple Choice

What is the volume of the rock?

• 50 mL

• 75 mL

• 25 mL

• 125 mL

Multiple Choice

Identify the volume of water.

• 22 mL

• 25 mL

• 15 mL

• 25 g

Multiple Choice

What is the volume of the chalk?

• 9 mL

• 19 mL

• 10 mL

• 20 mL

Multiple Choice

What is the volume of this prism?

• 20 ft³

• 8 ft³

• 40 ft³

• 11 ft³

Multiple Choice

What is the volume of this prism?

• 24 cm³

• 240 cm³

• 60 cm³

• 20 cm³

Density →

How tightly packed the molecules are in an object.

Formula: density = mass/volume
d=m/V - Usually g/cm3

●Doesn’t change when you cut or break an
object

●Decreases when you increase the volume -
you can do this by heating it up!

●Increases when you decrease the volume -
you can do this by applying pressure!

●More dense sinks - less dense rises (heat
rises!) “Denser Downer”

Multiple Choice

Frank has a paper clip. It has a mass of 9g and a volume of 3cm³. What is its density?

• 3 g/cm³

• 1/3 g/cm³

• 27 g/cm³

• 39 g/cm³

Multiple Choice

What is the density of water?

• 0 g/ml

• 1 g/ml

• 10 g/ml

• 100 g/ml

Multiple Choice

Put the liquids in order from most dense to least dense?

• 4, 3, 2, 1

• 1, 2, 3, 4

• 3, 4, 2, 1, 

• 4, 3, 1, 2

Multiple Choice

Which liquid is the least dense?

• oil

• water

• syrup 

• plastic bottle

Multiple Choice

What is the formula for density?

• density = mass x volume

• density = mass / volume

• density = mass + volume

• density = mass - volume

Multiple Choice

Why do some substances float on water?

• they are warmer than water

• they are cooler than water

• they are more dense than water

• they are less dense than water

Multiple Choice

Why does ice float?

• Liquid water is less dense than solid water.

• Solid water is less dense than liquid water.

• Gaseous water is less dense than solid water.

• Liquid water is less dense than gaseous water.

Multiple Choice

Look at this image.  Which object has the LOWEST density in water? How? 

• The Ping Pong Ball because it floats to the top 

• The bolt because it has sunk to the bottom

• The soda cap because it is not just full of air like the Ping Pong ball