Lecture 4 Flashcards
What is an ellipse?
An elongated circle with two foci. There is a major and minor axis describing the length and width of the ellipse.
What is Kepler’s first law?
The orbit of each planet around the sun is an ellipse with the sun at one focus.
What is Kepler’s second law?
As a planet moves around its orbit, it sweeps out equal areas in equal times (planet moves faster when closer to the sun).
What is Kepler’s third law?
More distant planets orbit the sun at slower average speed according to the relationship:
p^2=a^3
What is Galileo’s Theory of Relativity?
-Free motion is constant in speed and acceleration
-A free falling body is constantly accelerated
-A body sliding down a frictionless inclined plane experiences a constant acceleration of gsinθ
-It is not possible to tell if a vehicle is in constant motion
-There is no such thing as an observer at rest
What is speed?
The rate at which objects move: distance/time
What is velocity?
Speed but in a particular direction
What is acceleration?
Any change in velocity- speed or direction
What is momentum?
p=mv
A force changes the momentum of a body; a force causes an acceleration
What is eccentricity?
Eccentricity describes how deviated the ellipse is from a circle.
What is mass?
The amount of stuff in a body
What is weight?
The net force acting on a body
