SAVVAS, 3rd GRADE_ ELECTRIC FORCES

Open Ended

What do you know about electricity?

​ELECTRIC FORCES

​Vocabulary: electric forces, neutral, repel, attract, electric force, conductor, insulator, static discharge, source

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Swimmers are getting ready for a swim meet (race). Some clouds are in the sky, but the sun is shining at the pool. Then a lifeguard see the flash of distant lightning. He blows his whistle loudly. Everyone gets out of the pool right away. They move into the locker room before the storm arrives. Why is there so much concern?

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The electricity of lightning can travel very far from the storm. It can strike people and other objects 15 kilometers (10 miles) or more away from where the rain is falling. It can travel through water very easily. People can be seriously hurt if they are struck by lightning. That is why everyone must get out of the water when a thunderstorm is moving into the area. When you take part in outdoor sports, be very careful of lightning. ​

Reorder

Read the first paragraph again, then reorder the events to show that correct sequence of events that occurred during the swim meet.

Swimmers are getting ready for a swim meet (race). Some clouds are in the sky, but the sun is shining at the pool. Then a lifeguard see the flash of distant lightning. He blows his whistle loudly. Everyone gets out of the pool right away. They move into the locker room before the storm arrives. Why is there so much concern?

• A lifeguard sees the flash of lightning.

• He blows the whistle loudly.

• Everyone gets out of the pool.

1

2

3

• 1
• 2
• 3

​ELECTRIC CHARGE

​Vocabulary: positive, negative, neutral

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Think about it: What is the sequence of events that causes and electric shock? ​

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You walk on a carpet and then touch a doorknob. A small spark jumps between your hand and the doorknob. You may even hear a faint crackling sound. You experienced an electric shock! The overall cause of the shock is a force. ​

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All matter ​is made os small particles. One property of these particles is that they can have electric charges. Objects with protons have positive (+) charges. While electrons have negative (-) charges. When an object has an overall positive or negative charge, we say that it has an electric charge.

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Some objects have more​ positive particles than negative. We say that the objects has a positive charge. Likewise, if the object has more negative charges, then it has a negative charge. If the object has the same number of positive and negative charges, the object is neutral- or has no charge.

​​Postive Electric Charge

​​Negative Electric Charge

Draw

Draw an object that has a neutral charge.

​ATTRACT OR REPEL

​Vocabulary: positive, negative, neutral

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​When two objects with electric charge are close to one another, a force happens between them. If both objects have negative electric chargers, the two objects repel, or push away from each other. The same thing happens of both objects have a positive charge.

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Now, if one object has a positive charge and the other has a negative charge, each object attracts, or pulls on the other object. ​ This push or pull of charged objects is an electric force.

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Multiple Choice

Will these objects attract or repel one another?

• attract

• repel

Multiple Choice

Will these objects attract or repel one another?

• attract

• repel

Multiple Choice

Will these objects attract or repel one another?

• attract

• repel

Multiple Choice

Will these objects attract or repel one another?

• attract

• repel

Draw

Wrap- Up

How would you model (draw) two charges objects attracting, or repelling each other?

Draw your model using circles, squares, or anything abject you can think of- remember to add the charge as well.