Chapter 7 Flashcards
1
Q
Angular Measure
A
- Radius: constant over time
- Theta (0): changes over time
- Circular motion
2
Q
Arc Length
A
-Distance traveled along the circular path, theta is what defines this
3
Q
Radian
A
1 Radian= 57.3 degrees
4
Q
Angular Speed
A
- Rotational speed, how much angle is being covered
- SI: radians/second
- Common: revolutions
- 1 rev= 2pi radians
5
Q
Right hand rule
A
- Hand towards self=Clockwise= negative
- Hand away from self=Counterclockwise= positive
6
Q
Tangential Speed
A
- The linear speed of something moving along a circular path
- Farther from center= moves faster
- SI: m/s
7
Q
Period
A
- T
- Time it takes for one rotation, cycle, or revolution
- SI: s, s/cycle
8
Q
Frequency
A
- The number of rotations per second
- f
- SI: 1/s, hertz (HZ)
9
Q
Uniform Circular Motion
A
-Tangential speed= constant
10
Q
Centripetal Acceleration
A
- Acceleration directed toward the center of a circular path
- Created by change in magnitude of velocity, direction of velocity, or both
- SI: m/s^2
11
Q
Inertia
A
-A property of matter by which it continues in its existing state of rest or uniform motion in a straight line, unless that state is changed by an external force
12
Q
Centripetal Force
A
- The net force on an object in uniform circular motion
- Any combination of forces: gravity, friction, etc.
- SI: N
- Does not change KE or speed of object
13
Q
Radians per second to revolutions per minute
A
- 1 rev= 6.28 radians
- 60 seconds= 1 minute
14
Q
Kepler’ Laws
A
- Planets move in elliptical orbits, with the sun at one of the focal points (the law of orbits)
- A line from the sun to a planet sweeps out equal areas in equal lengths of time (the law of areas)
- The closer to the sun, greater the arc length, faster it has to move
- The square of an orbital period of a planet is directly proportional to the cube of the average distance of the planet from the sun (T^2 is directly proportional to r^3)
15
Q
Gravitational Force
A
- Field force
- Exert forces without coming into contact
- The mutual force of attraction between particles of matter
