Keplers 1st Law
The path of each planet around the Sun is
an elipse with the Sun at one focus.
Keplers 2nd Law
Each planet moves so that an imaginary
line drawn from the sun to the planet
During most collisions, we usually dont
know how force varies with time, so
analysis becomes either very difficult or
In ALL collisions, momentum is
If no heat is produced in the collision, then
Motion in a Gravitational Field
Another Look at Gravitational
We previously noted that it took work to lift
an object off the surface of the earth.
In more general terms, it takes work to
separate two objects.
Work can be calculated by
(Why are we attracted to that big
bright object in the sky)
Newtons Big Idea
Newton developed the idea that two bodies
exert a force on each other over a distance.
Specifically, sun and earth
He concluded tha
Goin around and around and .
An object that moves in a circle at
constant speed v, is said to experience
uniform circular motion.
The magnitude of the velocity remains
constant, but the direction is constantly