I don't
The time it takes or a rotating body to complete one rotation, be it spinning a top or the orbit of the earth, is called its
period
give an example of uniform circular motion and an example of nonuniform circular motion using a ceiling fan
uniform would be when the fan is going at a constant rate, nonuniform would be when it is starting or stopping
Torque is directly proportional to the moment arm (as arm increases, as does torque)
What was Aristarchus of Samos' view on the orbits of the sun and planets? Did he agree with Ptolemy of Alexandria
He believed in Heliocentric theory, unlike Ptolemy and most others who believed in geocentric theory
what is the name of the force that keeps an object in a circular path
centripetal force
(not centrifugal)
You are looking down at a clock sitting face up on a table, in what direction does the angular velocity of the second hand point?
Down toward the floor, perpendicular to plane of the hand's motion
(found using right hand rule)
What is Kepler's first law of planetary motion?
All planetary bodies orbit in an ellipse, with one of the focuses being the Sun
When a system is moving in nonuniform rotational motion, the angular velocity is changing, when the difference in angular velocity is taken over time, we find ______ designated with what symbol?
angular acceleration, designated with lower case alpha
At what angle should a force be applied to a rigid bar to produce the maximum Torque?
at a right angle with the bar
The vector quantity that causes rotational acceleration of a rigid system with a pivot point is called
Torque
what is the relationship between the direction of the position vector and the velocity vector (either angular or tangential)
they are perpendicular
What did cavendish do after calculating the value of the universal gravitation constant, G
he calculated the density of the earth, which was a major step into studying the structure of the earth
What is G in the formula for Newton's law of universal gravitation? Are it's units significant?
the universal gravitational constant, 6.674 x 10-11. The units are basically nonsensical as they just cancel out everything else in the formula
displacement in linear motion is analogous to what quantity in circular motion
change in theta (angle)
If a rotating object is in an accelerating reference frame, which vector is not perpendicular to the centripetal acceleration at any given instant?
position vector, tangential velocity, angular velocity, angular acceleration
position vector, it is the opposite direction and same position as the centripetal acceleration vector
s-1 is the SI unit for what measurement
angular speed, it means rad/s
Kepler's Second law
What is the relationship between the directions of angular velocity and angular acceleration when angular velocity is increasing? When it is decreasing?
Angular velocity's direction is found using the right hand rule. When it is increasing, angular acceleration is pointing in the same direction, when it is decreasing, angular acceleration points in the opposite direction.
Ptolemy added to Aristotle's model of heavenly motion with the concept of _______, meaning the small circles made by a body in orbit as it follows it's larger circular orbit
epicycles
if a ceiling fan at level 1 has a tangential velocity at the end of the blade of 50.0 m/s and level 2 increases it to 75.0 m/s over a matter of 5 s, what is the tangential acceleration?
5 m/s2
A ferris wheel car moves along its circular path at a tangential speed of 36 m/s. If the total height of the ferris wheel from the loading station to the highest the car goes is 500 m, what is the angular speed of the ferris wheel?
0.144 s-1 or rad/s
You spin a fish on the end of a hook around in a circle because you are an insane person. If you spin the fish in a circle with a radius of 0.75 m, what is the minimum tangential speed you must spin the fish to counteract gravity and not have the fish fall on your head?
2.71 m/s
If I spin the mass I've used in class (0.200 kg) in a 0.5 m radius circle at a speed of 5.0 m/s, what is the force of tension the string must endure to sustain the motion?
10 N
If the Martian moon Deimos has a semi-major axis of 23,460 km and an orbital period of 30.35 hours, then what would be the period of its sister moon Phobos if she has a semi-major axis of 9,377 km?
TP = 7.67 hours
5.56 x 10-11 N