Unit 5 - Rotation, Energy, Work & Momentum Flashcards
angular displacement
the change in the angle as an object rotates
theta = s/r
angular velocity
The angular displacement of an object divided by the time needed to make the displacement.
omega = delta(theta/delta(t)
angular acceleration
change in rate of rotation
alpha = delta(omega)/delta(t)
moment of inertia
the resistance to rotation
I=Emr^2
angular momentum
the quantity of rotation of a body, which is the product of its moment of inertia and its angular velocity.
torque
a turning or twisting force
collision
A situation in which two objects in close contact exchange energy and momentum
elastic collision
one in which there is no net loss of total kinetic energy
inelastic collision
a type of collision in which the kinetic energy after the collision is less than the kinetic energy before the collision
Momentum
The product of an object’s mass and velocity
p=mv
Impulse Momentum Theory
states that the impulse on an object equals the object’s final momentum minus the object’s initial momentum
Fdelta(t)=mdelta(v)
^ Impulse ^Change in momentum
Impulse approixmation
reasonably neglecting small forces during the brief time of the impulsive force
Internal forces
a force that acts on an object from the inside
External forces
forces that act on an object as a result of its interaction with the environment surrounding it
Isolated system
A system that can exchange neither energy nor matter with its surroundings.