Post on 11-Dec-2015
March 1 & 4Homework Due
Read & Study 12.1-12.4; do #1-7 p. 180 **Grade will be worth 5 points; ½ point per question and 1.5 points given to a randomly selected problem the teacher will grade on CORRECTNESS**
Tonight’s HW
Read & Study 12.4-12.6; do #8-13 p. 180 **Grade will be worth 5 points; ½ point per question and 2 points given to a randomly selected problem the teacher will grade on CORRECTNESS**
Do Now - Last chance to claim your poster / fix it if it fell down? Any left by next Wednesday will be thrown away!
- Take a clickerIn your notes, please write Q&A:Action: Earth pulls moon.What is the reaction?What is stronger – action, reaction, or same?What Law defends your answer?
Action: Earth pulls moon. - What is the reaction?
- What is stronger – action, reaction, or same?
- What Law defends your answer?
Action: Earth pulls moon.
What is stronger – action, reaction, or same?
1 2 3
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1. Action(Earth pulls moon)
2. Reaction (moon pulls Earth)
3. Same!
What law defends your answer?
1 2 3
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1. 1st Law2. 2nd Law3. 3rd Law
Google… • PHET Gravity and orbits• Click the first link• Run the simulation and complete the Lab
Activity Sheet. – This is due in 30 MINUTES for a grade – you
will (10 points based on completion)– Then, we will have a graded, individual, 30
point POST LAB to assess this lab activity.
#1 –Why did Newton think there must be a force acting on the moon?
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1. It moved in a straight line, not a circle
2. It moved in a circle, not a straight line
3. I had no clue how to answer this question
#2 What did Newton conclude about the force that pulls apples to the ground and the force that holds the moon orbit?
1 2 3
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1. They were different forces
2. They were the same force
3. I had no clue how to answer this question
#3 If the moon falls, why doesn’t it get closer to Earth?
1 2 3
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1. It has a large tangential speed, so it falls around Earth and not into it
2. It has a small tangential speed, so it falls around Earth and not into it
3. I had no clue how to answer this question
#4
• What is meant by tangential speed?– Popcorn…
#5
• How did Newton check his hypothesis that there is an attractive force between Earth and moon?– Popcorn…
#6
• What is required before a hypothesis can become a theory?– Popcorn…
#6
• What is required before a hypothesis can become a theory?– Popcorn…
#7 Since there is gravity between the planets and the sun, why don’t the planets crash into the sun?
1 2 3
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1. They have small tangential speeds, so they fall around sun and not into it
2. They have large tangential speeds, so they fall around sun and not into it
3. I had no clue how to answer this question
Choose the picture you think shows the gravity forces on the Earth and the Sun.
A. B. C. D. E.
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A. B. C. D. E.
How would these gravity forces change if the Sun got more
massive?
A. B. C.
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A. Increase
B. Decrease
C. Stay the same
How would these gravity forces change if the Earth was much
closer to the Sun?
A. B. C.
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A. Increase
B. Decrease
C. Stay the same
How would these gravity forces change if the Earth got much less
massive?
A. B. C.
0% 0%0%
A. Increase
B. Decrease
C. Stay the same
How would these gravity forces change if the Earth and Sun were
moved farther apart?
A. B. C.
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A. Increase
B. Decrease
C. Stay the same
Choose the picture of how the Earth would move if you “turned
off” the gravity forces.
A. B. C. D. E.
0% 0% 0%0%0%
A. B. C. D. E.
Changes to make to your post lab:• Make sure #2 and 4 say massive• Change the answer choices in #11 to
“enjoyable” rather than “useful”
• When you are done… Place in in box upside down; RETURN CLICKER IN ORDER; silently BEGIN your HW