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Kepler's Laws

Data below is a sample set of positional data of Explorer 35

in its eleiptical orbit around the Moon

(Reference: Activities in Astronomy by D.Hoff, L.Kelsey and J.Neff)

Click in here to see how the above animation is programed in mathematica

 

Kepler's Laws for the planets in an elliptical orbit around the Sun

1) Each planet moves around the Sun in an orbit that is an ellipse with the Sun at one focus.

2) Each planet moves so that an imaginary line joining the Sun and the planet sweeps out equal areas in equal times.

3) The squares of the periods of time required for for a planet to complete a trip around the Sun is proportional to the Cube of the average distance from the Sun.

 

Kepler's Laws WWW sites

 

 

Activity No 13

Kepler's Laws for a satellite in an elliptical orbit around the Moon

1) Each satellite moves around the Moon in an orbit that is an ellipse with the Moon at one focus.

2) Each satellite moves so that an imaginary line joining the Moon and the satellite sweeps out equal areas in equal times.

3) The squares of the periods of time required for for a planet to complete a trip around the Moon is proportional to the cube of the average distance from the Moon.

 

Activity Report

 

Use the above animation to answer the following questions. ( I am still working on it )

 

Kepler's 2nd Law

Pictures (1 and 2 )

Pictures (3 and4)

Instructions: Use the above pictures (1-2) and (3-4) to calculate the following values in step 1 and step 2. Note: (t2-t1) = 1.8 hrs and (t4-t3) = 1.8 hrs.

Question 1: Are the above ratio approximately equal to 1. If not, then what is the source of our errors. Explain. Calculate the percentage error.

Question 2: Is the angular momentum conserved. Explain the consevation of an agular momentum.

Question 3: Explain why the spacing between dots in this fiqure are not equal.

 

Kepler's 3rd Law

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