Planetary Orbit Simulation Lab Manual
Name:
Planetary Orbit Simulator – Student Guide
Background Material
Answer the following questions after reviewing the “Kepler's Laws and Planetary
Motion” and “Newton and Planetary Motion” background pages.
Question 1: Draw a line connecting each law on the left with a description of it on the right. only a force acting on an object can change its motion
Kepler’s 1st Law
Kepler’s 2nd Law
planets move faster when close to the sun
Kepler’s 3rd Law
Newton’s 1st Law
planets orbit the sun in elliptical paths planets with large orbits take a long time to complete an orbit
Question 2: When written as P2 = a3 Kepler's 3rd Law (with P in years and a in AU) is applicable to …
a) any object orbiting our sun.
b) any object orbiting any star.
c) any object orbiting any other object.
Question 3: The ellipse to the right has an eccentricity of about …
a) 0.25
b) 0.5
c) 0.75
d) 0.9
Question 4: For a planet in an elliptical orbit to “sweep out equal areas in equal amounts of time” it must …
a) move slowest when near the sun.
b) move fastest when near the sun.
c) move at the same speed at all times.
d) have a perfectly circular orbit.
NAAP – Planetary Orbit Simulator 1/8
Question 5: If a planet is twice as far from the sun at aphelion than at perihelion, then the strength of the gravitational force at aphelion will be ____________ as it is at perihelion.
a) four times as much
b) twice as much
c) the same
d) one half as much
e) one quarter as much
Kepler’s 1st Law
If you have not already done so, launch the NAAP Planetary Orbit Simulator.
•
Open the Kepler’s 1st Law tab if it is not already (it’s open by default).
•
Enable all 5 check boxes.
•
The white dot is the “simulated planet”. One can click on it and drag it around.
•
Change the size of the orbit with the semimajor axis slider. Note how the background grid indicates change in scale while the displayed orbit size remains the same.
•
Change the eccentricity and note how it affects the shape of the orbit.
Planetary Orbit Simulator – Student Guide
Background Material
Answer the following questions after reviewing the “Kepler's Laws and Planetary
Motion” and “Newton and Planetary Motion” background pages.
Question 1: Draw a line connecting each law on the left with a description of it on the right. only a force acting on an object can change its motion
Kepler’s 1st Law
Kepler’s 2nd Law
planets move faster when close to the sun
Kepler’s 3rd Law
Newton’s 1st Law
planets orbit the sun in elliptical paths planets with large orbits take a long time to complete an orbit
Question 2: When written as P2 = a3 Kepler's 3rd Law (with P in years and a in AU) is applicable to …
a) any object orbiting our sun.
b) any object orbiting any star.
c) any object orbiting any other object.
Question 3: The ellipse to the right has an eccentricity of about …
a) 0.25
b) 0.5
c) 0.75
d) 0.9
Question 4: For a planet in an elliptical orbit to “sweep out equal areas in equal amounts of time” it must …
a) move slowest when near the sun.
b) move fastest when near the sun.
c) move at the same speed at all times.
d) have a perfectly circular orbit.
NAAP – Planetary Orbit Simulator 1/8
Question 5: If a planet is twice as far from the sun at aphelion than at perihelion, then the strength of the gravitational force at aphelion will be ____________ as it is at perihelion.
a) four times as much
b) twice as much
c) the same
d) one half as much
e) one quarter as much
Kepler’s 1st Law
If you have not already done so, launch the NAAP Planetary Orbit Simulator.
•
Open the Kepler’s 1st Law tab if it is not already (it’s open by default).
•
Enable all 5 check boxes.
•
The white dot is the “simulated planet”. One can click on it and drag it around.
•
Change the size of the orbit with the semimajor axis slider. Note how the background grid indicates change in scale while the displayed orbit size remains the same.
•
Change the eccentricity and note how it affects the shape of the orbit.