step 2 - determine what formula you want to use. It should have what you need as part of it ( what you want
may be in the middle of the formula)
step 3 - list the information you have, do you have everything required by the formula you want to use?
step 4 - if yes, take the formula you chose, plug and chug. if no will another formula work? Or else, can you find what you need u a different formula?
Here is a list of equations (do some of these show up as fractions? they are supposed to.)
NOTE: For Keplers 3rd law - anytime you see the proportionality symbol, you should be able to rewrite the proportion in the other two forms.
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Question 1
1.
A ball of mass 1 kg dropped on planet Ploof accellerates at a rate of 5 m/s2 . find the force of gravity on the ball. Which of the following are you given?
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Question 2
2.
A ball of mass 1kg dropped on planet Ploof accellerates at a rate of 5 m/s2. Find the force of gravity on the ball. Considering what you are given, which of the following formulas will you use?
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Question 3
3.
Find the force of gravity on the ball
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Question 4
4.
Measuring lengths of shadows in wells, we can determine that the radius of planet Ploof is 5,000,000 m. We gave up using the units Floops and Polfs, so we get to use G = 6.8 x 10-11 Nm2/kg2 . Using
Do you have everything you need to find the mass of Ploof
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Question 5
5.
Giant hint on the correct answer for question 4. Find the mass of Ploof (you will need to solve the formula given for the mass.
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Question 6
6.
Practice. Ploof is 54 polfs from the sun, and takes 400 days to revolve around the sun. The closest planet, Neighbor, is 34 polf from the sun. How many days will it take to revolve around the sun?
Find one of the formulas that will give you what you need. plug in the values. don't solve yet.
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Question 7
7.
Take the following formula (again, for some reason these are not showing up as fractions, but they should be). These are equation we haven't spent much time on. That shouldn't matter.
A spaceship burns to get to a velocity of .5 light year/year. The burns ends as soon as the spaceship is beyond the reach of the sun's gravitational field, 2 light years from the sun. You will soon be asked "How long does it take the spaceship, now going at a constant velocity, to be 4 light years from the sun." before that though, please match the numbers given with the information needed for the formula.
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Question 8
8.
Take the following formula (again, for some reason these are not showing up as fractions, but they should be). These are equation we haven't spent much time on. That shouldn't matter.
A spaceship burns to get to a velocity of .5 light year/year. The burns ends as soon as the spaceship is beyond the reach of the sun's gravitational field, 2 light years from the sun. now answer "How long does it take the spaceship, now going at a constant velocity, to be 4 light years from the sun."
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Question 9
9.
Use the formulas at the top - the moon has an orbital period of 27 days and has a semi major axis of 3.8 x105km. Find the proportionality constant of the earth moon system.
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Question 10
10.
use info from question 9. A satellite zips around the earth in 4 days. Set up two different ways to use Keplers law to find the semi-major axis of the satellite's orbit. Don't solve, just set the formula and plug in everything you know