Measuring Massby Georgeann Wright

Mass is……….. a physical

property of matter

It is the amount of matter in an object.

We measure mass in grams.

Mass

A friendly reminder from Frogger: • A frog has the

same mass on the Earth and on the Moon.

Weight is different….

It’s the amount of the pull of gravity on an object.

• A frog weighs less on the moon than on the Earth because there is less gravity on the moon.

Boy, I could jump REALLY high on the

moon.

Mass

Is measured with a 3-beam balance and is

measured in grams.

Weight Is measured

with a SPRING SCALE.

It is measured in Newtons.

To measure mass….

We use a 3-beam balance. The unit is grams (g).

http://www.wisc-online.com/Objects/ViewObject.aspx?ID=GCH202

Let’s look at a 3-beam balance.

Measurement tray: Holds the mass to be measured.Rider Beams: Hold the weights that can be slid and slipped into grooves.Riders: The actual weights ( 1gram, 10 grams, 100 grams)Adjustment Knob: moves the pointer up and down to balance it.Pointer: must point directly at the zero mark when balanced

Practice on a 3-beam balance…at this website.

First move all weights to the far left at the “0”.

Next, use the largest weights first.

Make certain that the two arrows meet.

http://www.touchspin.com/chem/DisplayTBB.html

You will measure the mass of the following items at your group:

1. Full soda can2. Empty soda can3. Metric ruler4. Paper clip5. 2 objects of your choice

Test yourself on your knowledge.

1. What is the function of the beams with riders?2. What is the function of the adjustment knob?3. What is the function of the pointer?4. What is the function of the measurement tray?5. Explain the difference between weight and mass