OBJECTIVE: Explain, in terms of protons and electrons, why a charged object is attracted to or repelled by another object.

Discuss with your elbow partner: Where are each of the following located in the picture? protons, neutrons, electrons

Discuss with your elbow partner: What is the charge of each of the following? protons, neutrons, electrons

Discuss with your elbow partner: Describe if each of the following will attract or repel. 2 protons a proton & an electron 2 electrons

1 complete sentence in each box Describe what you see. Do they STICK TOGETHER or PUSH APART? What did you hear as you charged the object? Do they ATTRACT or REPEL? Are they the SAME charge or OPPOSITE charge?

Discuss together: What is happening in each picture?

Discuss with your elbow partner: What is happening in each picture?

Discuss with your elbow partner: What is happening in each picture?

Answers: 1) electrons 2) skin, plastic; POSITIVE, NEGATIVE 3) ATTRACT, POSITIVE, AWAY FROM 4) REPEL, OPPOSITE

Write 1-2 complete sentences for each picture. Explain using these words: proton, electron, positive, negative, neutral

Both objects are neutral Equal number of protons & electrons (+) (-) Balloon gets electrons from hair  - Paper becomes more + near balloon Protons (+) in the paper attract to electrons (-) in the balloon

Discuss with your elbow partner: For the balloon/water demo: Explain what you observed using the concept protons, electrons, and charges.

EXTRA CHALLENGE: For the balloon/water demo: Why does the whole stream of water bend when just the molecules on the surface are attracted to the balloon? Hint: Think back to the Cork & Liquids Labs. What properties of water do you think are important? Rexamine surface tension, polarity of water, and cohesion