Flashcards in Engineering - Rotational Dynamics Deck (20)
Define angular displacement
Angle turned through
Define angular velocity
Rate of change of angular displacement
Define angular acceleration
Rate of change angular velocity
How is angular acceleration determined for a rotating object that changes angular speed?
Angular version of suvat
How is speed and acceleration at a point on a rotating object worked out?
Angular version multiplied by radius
Angular displacement against time graph, what is gradient?
Angular velocity against time graph, what is gradient and area under?
Gradient: angular acceleration
Area under: angular displacement
Force times perpendicular distance from the axis to the line of action of the force
An object's resistance to change of its motion
What is the moment of inertia?
Moment of inertia, I, of a body about a given axis is defined as Σmr^2 for all the points in the body, where m is the mass of each point and r its perpendicular distance from the axis
For a hoop of mass M and radius R, what is the moment of inertia?
For a disc of mass M and radius R, what is the moment of inertia?
For a uniform beam of length L and mass M, what is the moment of inertia through its centre?
For a uniform beam of length L and mass M, what is the moment of inertia through its end?
What is the kinetic energy of a rotation object proportional to?
Moment of inertia about axis of rotation
Square of its angular speed
How can moment of inertia for a fly wheel be calculated?
Using 1/2 (Iω^2 + Mv^2) = Mgh
What is angular momentum?
Produce of moment of inertia and angular velocity
What is torque in relation to angular momentum?
Torque is rate of change of angular momentum
Define angular impulse
Change in angular momentum