Test practice

Some pre-test problems.  Test will be next Thursday (E block) and Friday (A block).

These will NOT be collected.

1.  Consider the planet Jupiter.  The semi-major axis of orbit is 5.2 AU and its mass is 318 times that of Earth.  The radius of Jupiter is about 11.2 times that of Earth.  Use that information to find the following:

a.  time for Jupiter to orbit the Sun once

b.  surface gravity on Jupiter * (A block hasn't covered this yet - see notes)

c.  approximate speed of Jupiter in orbit around the Sun (in m/s).  You can approximate the orbit as circular, or use the fact that the semi-minor axis is 5.1973 AU.
d.  the force of gravity (on average) between Jupiter and the Sun (m = 2 x 10^30 kg)

The following will not be on the upcoming test/quest.  Now, if you know that the eccentricity of Jupiter’s orbit is 0.049, you can find other things.  By the way, the easiest way to relate eccentricity (unlike the definition I gave you in class) is:

ecc = f/a

In this definition, f is the distance between the center of the ellipse and either focal point.  The semi-major axis is still a.  Find the following:

e.  the closest that Jupiter gets to the Sun (in AU)

f.  the furthest that Jupiter is from the Sun (in AU)

2.  Newton review

A spring-loaded ball (mass = 0.04 kg) is shot up into the air.  The ball and spring are in contact for 0.1 seconds  and during this time, the spring exerts an average force of 75 N on the ball.  Find:

a.  the maximum speed of the ball (“muzzle velocity”)

b.  how high the ball can travel

c.  how long it takes the ball to reach max height

The upcoming test will likely have 3 questions:  two like the above, and a third where you choose 1-2 things to write about (out of 3 or 4).  Other topics worth reviewing are:  the rocket lab (and all the discussion on drag that we had), Kepler's 3 laws, and Newton's 3 laws (the theory).

FYI:

https://www.youtube.com/watch?v=C4pcg7bXgmU