Magnetic ForceTypes/Properties of Forces and

Motion

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This week’s lessons are designed to reinforce:State Science Standard

IV Force, Motion, and Mechanical Energy

A. Relative Motion/Position:An object’s position can be described relative to another object.

B. Types/Properties of Forces and Motion:Forces can be gravitational, electrostatic, or magnetic.

C. Interactions of Forces and Motions:Magnets attract and repel each other and certain kinds of metals.

Teacher Page

We suggest that students keep a journal.

It is critical for students to use writing skills to explain answers. When you see this symbol students should use their journals.

Activity 1

GravitationalForce

What will happen when the eraser is dropped or the apple falls off of the stool?

Click for answer

The objects fall or are forced down.

Why does this happen?

Click for answer

Gravity is the force that pulls things down to the earth.

Predict what will happen when the objects are placed on the balance scale? Tell why you think this will happen.

Answer next

The side of the scale holding the apple was forced down because the apple has more mass and gravitational pull.

Activity 2

ElectrostaticForce

Using a balloon and a wool sweater, how can you get the balloon to cling to the chalkboard? What causes this to happen?

When you rub the balloon on the sweater, static electricity is produced causing the balloon to be attracted to the chalkboard.

Can you get your hair to standup?

Have you tried picking paper up with a comb?

Have you tried an experiment with a balloon, a piece of wool, salt, and pepper?

Tell about other ways static electricity is produced. After writing, click for some ideas.

Activity 3

MagneticForce

A magnet is a piece of metal that pulls or attracts things which have iron or steel in them. The most common magnets are in the shape of a bar or horseshoe.

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Draw what will happen when the bar magnet comes in contact with the iron filings. Explain why this happens.

iron filings

bar magnet

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The magnet is surrounded by a force field which attracts the iron filings, especially at the poles.