Chapter 5
Uniform Circular Motion and Gravitation
By Boundless
![Thumbnail](../../../../../figures.boundless-cdn.com/30812/square/figure-07-01-01ab.jpeg)
Uniform circular motion is a motion in a circular path at constant speed.
![Thumbnail](../../../../../figures.boundless-cdn.com/16988/square/figure-07-06-02a.jpeg)
Newton's universal law of gravitation states that every particle attracts every other particle with a force along a line joining them.
![Thumbnail](../../../../../figures.boundless-cdn.com/17157/square/figure-07-03-03a.jpeg)
In an "ideally banked curve," the angle
![Thumbnail](../../../../../figures.boundless-cdn.com/17109/raw/angular-velocity.jpg)
The rotational angle is a measure of how far an object rotates, and angular velocity measures how fast it rotates.
![Thumbnail](../../../../../figures.boundless-cdn.com/16960/square/figure-07-02-01a.jpeg)
Centripetal acceleration is the constant change in velocity necessary for an object to maintain a circular path.
![Thumbnail](../../../../../figures.boundless-cdn.com/16959/square/figure-07-03-01a.jpeg)
A force which causes motion in a curved path is called a centripetal force (uniform circular motion is an example of centripetal force).
![Thumbnail](../../../../../figures.boundless-cdn.com/17015/square/1.jpeg)
Tides are the rise and fall of sea levels due to the effects of the gravity exerted by the moon and the sun, and the rotation of the Earth.
![Thumbnail](../../../../../figures.boundless-cdn.com/17016/square/corioliskraftanimation.gif)
The Coriolis effect is a deflection of moving objects when they are viewed in a rotating reference frame.
![Thumbnail](../../../../../figures.boundless-cdn.com/17018/raw/coriolis-effect10.jpg)
Tidal and Coriolis forces may not be obvious over a small time-space scale, but they are important in meteorology, navigation, and fishing.
![Thumbnail](../../../../../figures.boundless-cdn.com/17575/raw/slawofuniversalgravitation.jpg)
Objects with mass feel an attractive force that is proportional to their masses and inversely proportional to the square of the distance.
![Thumbnail](../../../../../figures.boundless-cdn.com/31427/square/640px-shell-diag-1.jpg)
The Shell Theorem states that a spherically symmetric object affects other objects as if all of its mass were concentrated at its center.
![Thumbnail](../../../../../figures.boundless-cdn.com/17583/square/earth-g-force.jpg)
When the bodies have spatial extent, gravitational force is calculated by summing the contributions of point masses which constitute them.
![Thumbnail](../../../../../figures.boundless-cdn.com/16987/square/500px-ellipse-latus-rectum.jpg)
Kepler's first law is: The orbit of every planet is an ellipse with the Sun at one of the two foci.
Kepler's second law states: A line joining a planet and the Sun sweeps out equal areas during equal intervals of time.
![Thumbnail](../../../../../figures.boundless-cdn.com/17013/raw/kepler-third-law-diagram.jpg)
Kepler's third law states that the square of the orbital period of a planet is directly proportional to the cube of the semi-major axis of its orbit.
![Thumbnail](../../../../../figures.boundless-cdn.com/17098/square/721px-voyager-path.jpg.jpg)
An orbital maneuver is the use of propulsion systems to change the orbit of a spacecraft (the rest of the flight is called "coasting").
![Thumbnail](../../../../../figures.boundless-cdn.com/17089/square/799px-orbitalaltitudes.jpeg)
Natural satellites are celestial objects that orbit a larger body; artificial satellites are manmade objects put in the orbit of the Earth.