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Level 99

## Ignore words

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matter, motion, causes
What are the core concepts of physics
translation
linear movement
rotation and reflection
What do you need to move a real shape somewhere
reflection
a wave strikes a boundary and bounces back
An angle whose arc length is equal to its radius
the angle when the arc around the circle equals the radius
translation and rotation
what do objects with form need to fully explain their motion
rotational kinematics
our units are built up from seconds for time and radians for angle
frame of reference
assists one in physics in which one chooses a place (point) a measure it against changes in position.
counter clockwise
when is torque positive
clockwise
Angular velocity is negative if the rotation is . . .
s
arc
angular velocity
represented by a lower case omega (ω)
What is angular velocity measured in
Tangential velocity
A velocity parallel to the Earth's surface
Angular acceleration
represented by a lower case alpha (α)
What is angular acceleration measured in
our direction keeps changing
Even with a constant tangential velocity why do we still accelerate
centripetal acceleration
a = centripetal acceleration
centripetal
center seeking
centripetal accelration
emerges from uniform circular motion that seeks the center because tangential velocity keeps changing direction
meters per second squared
what is centripetal acceleration measured in
it only feels like we're pulled away because our frame of reference; Newton's first law still applies
Why do we feel pulled away from the center when in uniform circular motion if the centripetal acceleration is center seeking
Torque
A "force" that causes rotation because it is exerted at a distance from the axis of rotation.
inertia
_______ is the property of an object that leads it to resist any change in motion
moment of inertia
rotational inertia; depends on the mass, radius, and axis of rotation
angular momentum
analogous to momentum; if the net torque on a system is zero then the angular momentum is conserved
Center of mass
same as center of gravity
a parabola
what does the center of mass follow when in projectile motion
if it can move down to topple
what decides if an object's center of mass is unstable
it is moves up to topple
What decides if an object's center of mass is stable
Why is an equilibrium unstable
because any displacement lowers the center of mass
Why is an equilibrium stable
because work must be done to raise the center of mass
Angular displacement
displayed as the change in theta (∆θ)