2015-2016 WINTER - EXTRA CREDIT
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Extra credit is due on the first day back after winter-break.
Only quality work receives full credit.
The point values below give the maximum point value for each project. While you
will not lose points for a few minor errors, you should not expect to receive the full
point value if your work is sloppy or incomplete.
You can complete any combination of the projects, but you may earn a maximum
of 20 points total. Individual projects also have their own limits.
I RESEARCH PAPER.
Max 10 points each
Your research paper has to be 3-5 pages of text + cover sheet. The paper must be typed (using 11-point size
and double space, font type – Arial, Times). You should include labeled sketches and diagrams (with captions)
illustrating and clarifying the concept. No “copy-paste”! Include references. You should make a 5-10 minute
presentation on the paper, a demo is recommended. Be prepared to answer questions from the class. You must
schedule a day to present your paper in advance.
1. “Weightlessness” in spacecraft orbiting the Earth.
8. Space and time travel.
2. Physics of pole vaulting.
9. Physics of skateboard.
3. Physics of football.
10. Physics of cars.
4. Simulated gravity.
11. Physics of motorcycles.
5. Center of mass (gravity) and stability.
12. Physics of surfing.
6. Ocean tides.
13. Physics of music.
7. Black holes.
14. ______________________
II WRITE A PHYSICS POEM, SONG, OR CARTOON.
Max 5; 2 points each.
Write a poem, song, or cartoon. You may decide on the format of your work of art. A short, simple poem such as
a haiku will receive a maximum of 1 point, whereas a longer and more complex work of art may receive up to 5
points. Your work should be relevant to course material. Illustrate your poem or song. Give a caption for your
cartoon. Design and format your work. Bring a copy to class to put on the display.
III PRESENT A PHYSICS NEWS STORY.
Max5; 2 points each.
Find an article about a current physics-related news story. Write a 200-250 word summary of the article (typed,
in your OWN WORDS), attach a copy of the article to the summary, make a ~5 minute presentation on the content
of the article. Be prepared to answer to the questions from the class. You must schedule a day to present your
article in advance.
IV
TIMELINE OF HISTORY OF PHYSICS. Max 10 points
In a poster form give the important milestones/discoveries of physics. Briefly describe the importance of each of
them in the context of the world history. Include scientists. You can pick a certain century OR start from the
beginning of recorded history until today.
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PROBLEMS – NEWTON’S LAWS.
1 point each - problems 1-12; 2 points each - problems 13 -15.
Neatly show your answers on a separate sheet of paper. All answers must be expressed as complete
sentences and be correct to receive credit. Include sketches. Problems 10-15 must be properly formatted
(“six boxes”), have full solutions and be correct to get credit.
1. Consider two identical cans, one filled with lead and the other empty. The cans are located far in space at a place
where they are "weightless". Describe a method of determining which can has the greater mass.
2. Consider hitting a baseball with a bat. If we call the force of the bat against the ball the action force, identify the
reaction force.
3. A strongman is standing between two identical freight cars of equal mass. He pushes on both cars while his feet
are off the ground. Is it possible for him to set either of the cars in greater motion than the other? Why or why
not?
4. In a tug-of-war, what is the net force acting on the rope when the participants each pull with opposing forces of
500 N? What is the tension force within the rope? Explain!
5. In terms of inertia, what is the disadvantage of a lightweight camera when snapping the shutter? Why is a
massive tripod preferred by most photographers?
6. What is meant by "free fall"? Why doesn't a heavy object fall faster than a lighter object when both are in a state
of free fall?
7. If we find a body that we know to be acted on by a force, but that is not moving, what inference can we draw
about its state of motion?
8. Do you find it easier to walk on a carpeted floor than one having a polished smooth surface? Why?
9. How does the weight of a falling body compare to the air resistance it encounters just before it reaches terminal
velocity? ___________ After?___________ Explain both answers.
10.
A freight train has a mass of 1.5 x 107 kg. If the locomotive can exert a constant pull of 7.5 x 105 N, how
long does it take to increase the speed of the train from rest to 80. km/h? (Ans: 4.4 x 102 s)
11.
A 2.00 x 103 kg car is slowed down uniformly from 20.0 m/s to 5.00 m/s in 4.00 s. (a) What average total
force acted on the car during this time, and (b) how far did the car travel during this time?
(Ans: -7.50 x 103 N; 50.0 m)
12.
A 5.0-kg bucket of water is raised from a well by a rope. If the upward acceleration of the bucket is 3.0
2
m/s , find the force exerted by the rope on the bucket. (Ans: 64 N)
13. Find the tension in each cable supporting the 600. N cat burglar.
(Ans: 997 N-inclined; 796 N-horizontal)
14. An object with mass m1 = 5.00 kg,
resting on a frictionless horizontal table,
is connected to a cable that passes over a
pulley and then is fastened to a hanging
object with mass m2 = 10.0 kg, as in
figure. Find the acceleration of each
object and the tension in the cable.
(Ans: 6.53 m/s2; 32.7 N)
15. Find the acceleration experienced by each of the
two objects shown if the coefficient of kinetic friction
between the 7.00-kg object and the plane is 0.250.
(Ans: 3.30 m/s2 )
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