Level 92 Level 94
Level 93

## Ignore words

Check the boxes below to ignore/unignore words, then click save at the bottom. Ignored words will never appear in any learning session.

Ignore?
Axis of Rotation
The center for all circles of rotation as well as for all of the points on the circles of rotation.
angular velocity and angular acceleration
All points in a rigid object rotate with the same . . .
Rigid Object
An object with a definite shape where the particles composing it stay in fixed positions relative to each other.
linear velocity
. . . is greater for points rotating farther from the axis of rotation.
counter-clockwise
Angular velocity is positive if the rotation is . . .
clockwise
Angular velocity is negative if the rotation is . . .
linear acceleration
An apple falling to the earth is what kind of acceleration?
Total acceleration for a rotating object is the vector sum of . . .
centripetal acceleration
a = centripetal acceleration
Centripetal acceleration points towards . . .
the center of the point's circular path.
Centripetal acceleration is greater . . .
the farther the point is from the axis of rotation.
Frequency
#cycles/second
period
the time required to make one complete rotation
parallel
Tangential acceleration is . . . to velocity
Perpendicular
A wave in which the vibration of the medium is _______ to the direction in which the wave travels is called a transverse wave.
Rw
If there is rolling without slipping, the C.O.M. is equivalent to . . .
zero
The oxidation number of an atoms that is not bonded is _______
less than or equal to Rw
If there is both rolling and slipping, the C.O.M. is . . .
C.O.M. Frame
The frame of reference in which the center-of-mass is not moving.
centripetal motion
In the C.O.M. frame, points on the rim move at constant speed and execute . . .
twice
In rolling without slipping, the top of a rim rolling on the ground spins . . . as fast as the center.
stationary
In rolling without slipping, the bottom of a rim rolling on the ground is . . .
lever arm
distance from the axis of rotation
the lever arm
Angular acceleration is directly proportional to . . .
Torque
A "force" that causes rotation because it is exerted at a distance from the axis of rotation.
no change in rotation
Forces applies parallel to the axis of rotation cause . . .
force to cause a change in rotational motion
The closer to the hinge the greater the . . .
Line of Action
Is parallel to the force and passes through the point of contact where the force acts.
Right Hand Rule for Torque
Point fingers from the axis of rotation to the point of application to the force, curl fingers into the direction in which the force acts, and the thumb then points along the torque.
positive or counter-clockwise
Out of the page torque is . . .
negative or clockwise
Into the page torque is . . .
moment of inertia
rotational inertia; depends on the mass, radius, and axis of rotation
a change in rotational motion
Net torque produces . . .
Rotational inertia depends on mass and . . .
how mass is distributed from the axis of rotation
an object rotation around an axis
Rotational Kinetic Energy is produced by . . .
Total Kinetic Energy
The sum of the translational and rotational kinetic energy of an object.
Potential Energy
(mass) x (g) x (height)
the constant of proportionality (x)
The more compact an object is, the smaller . . .
In rolling without slipping, the speed of an object rolling down a hill is . . . at the bottom.
Law of Conservation of Angular Momentum
The total angular momentum of a rotating object remains constant if the net torque acting on it is zero.
the object will speed up
If torque is parallel to the angular momentum . . .
the object changes direction at a constant speed
When the acceleration is perpendicular to the velocity . . .
the angular momentum's magnitude increases
When torque is parallel to angular momentum . . .
the angular momentum's magnitude decreases
When torque is anti-parallel to angular momentum . . .
Precession
When torque and angular momentum are perpendicular to each other such that the angular momentum changes direction at a constant speed.
spin up to conserve angular momentum
If the rotational inertia of an object decreases while the net torque acting on the object is zero, the object must . . .
spin down to conserve angular momentum
If the rotational inertia of an object increases while the net torque acting on the object is zero, the object must . . .
external
Only . . . torques produce change in angular momentum of a system.
Stable Equilibrium
An object is perturbed from equilibrium and returns to equilibrium.
Static equilibrium
A state of motion where an object is at rest
Dynamic equilibrium
A state of motion where an object is moving with constant velocity
equilibrium
1)starting point of SHM, object is in _______, fnet equals zero
the frame of reference
Static equilibrium can change to dynamic with a change in . . .