Transcript PHYS111_21 - MrLaFazia.com

Conceptual Physics
THURSDAY November 4th, 2010
LESSON GOALS:
• Continue our series of Lunar discussion questions as a class
• Discuss the Big Bang Theory and its implications
• Watch video segments on the Big Bang (Theory of, Evidence for, and
Replication of)
• Demonstrate Gravity Simulator program
• solar system & earth-moon system simulations
• Share thoughts on gravity Discussion Prompt
• Calculate Earth-Moon gravitational force magnitude
http://mrlafazia.com/PHYS111/lessons/201011Fall/PHYS111_21.ppt
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Lunar Study Questions
We will now continue our look at some of the
important questions regarding our nearest
celestial neighbor—Luna.
Recall that these questions relate prior content
and experiences to the Moon-Earth-Sun
system.
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Lunar Study Questions 9-13
9) How does a partial or total eclipse of the Sun occur?
10) How does a partial or total eclipse of the Moon
occur?
11) When does a full moon occur?
12) How does the Moon’s diameter compare to the
Earth’s?
13) Why do the Sun and Moon appear to be
approximately the same size “in the sky” even
though the Sun is able to encompass millions of
Moons within itself?
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Lunar Study Questions 14-18
14) What might happen if the Earth did not rotate on
its own axis as it revolves around the Sun?
15) Explain what happens with high and low tides.
16) Considering the Sun’s effects (about 1/3,
gravitationally, as the Moon’s), when would you get
the biggest difference between high and low tides?
17) Why is the Moon getting further and further away
from the Earth (i.e., why is it “less tightly bound”)?
18) How is the Moon (theoretically) supposed to “meet
its end” if given enough time…?
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Discussion: The Big Bang
• Discussion: “What is the Big Bang Theory and
what does it propose”?
– “How does this relate to the idea of Energy
Conservation”?
– “Is there just one version of the Big Bang Theory”?
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Video Segments: The Big Bang
• Segment 1: Theory Behind the Big Bang (3 mins)
• Segment 2: Evidence for the Big Bang (6 mins)
• Segment 3: Replicating the Big Bang (3 mins)
– After each clip we may discuss what was presented.
• Any questions which arose should be brought up during
that time.
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Gravity Simulator: Part 1
Our Solar System and the importance of
gravitational stability…
“What happens when we delete a planet?!”
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Gravity Simulator: Part 2
• Making our OWN Earth-Moon system
– Each group must research one aspect of the Moon…
•
•
•
•
•
Size (in kilometers) (meaning Diameter)
Mass (in kilograms)
Semi-Major Axis (in kilometers) (relates to distance from Earth)
Eccentricity (how “elliptical” its orbit is)
Inclination (where it is in relation to the Earth’s equator)
– “What effect does the Earth have on the Moon”?
– “What effect does the Moon have on the Earth”?
– “How long does it take the Moon to complete its orbit”?
• “Does this make sense”??
– “What happens when we delete the Earth?!”
• MAKE PREDICTION and THEN test it.
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Discussion Prompt: gravity
“It is often a misconception that other planets
do not exhibit gravity of their own. Think
about space exploration. How would other
planets NOT “having” gravity make space
travel MORE DIFFICULT”?
Think about this individually (make some notes
for your own reference) and then we will
share our ideas and discuss.
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Calculation: Earth-Moon attraction
• Using Newton’s Law of Universal Gravitation,
work out the gravitational force acting
between the Earth and the Moon.
– “Does it matter which object’s ‘Point of View’ you
consider”?
• WHY or WHY NOT?
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Recommended Reading:
• p. 105, Sections 6.1 – 6.5, 6.7 – 6.11
Note: The text does not offer much specific help on
Earth and Space topics, so we will rely mostly on outside
sources for our references for the majority of this unit.
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Looking Ahead:
• Next class we will discuss Solar Evolution and get
some more practice on the Law of Universal Gravitation.
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