Engineering - Rotational Dynamics Flashcards Preview

AQA A-Level Physics > Engineering - Rotational Dynamics > Flashcards

Flashcards in Engineering - Rotational Dynamics Deck (20)
Loading flashcards...
1

Define angular displacement

Angle turned through

2

Define angular velocity

Rate of change of angular displacement

3

Define angular acceleration

Rate of change angular velocity

4

How is angular acceleration determined for a rotating object that changes angular speed?

Angular version of suvat

5

How is speed and acceleration at a point on a rotating object worked out?

Angular version multiplied by radius

6

Angular displacement against time graph, what is gradient?

Angular velocity

7

Angular velocity against time graph, what is gradient and area under?

Gradient: angular acceleration
Area under: angular displacement

8

Define torque

Force times perpendicular distance from the axis to the line of action of the force

9

Define inertia

An object's resistance to change of its motion

10

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

11

For a hoop of mass M and radius R, what is the moment of inertia?

MR^2

12

For a disc of mass M and radius R, what is the moment of inertia?

1/2 MR^2

13

For a uniform beam of length L and mass M, what is the moment of inertia through its centre?

1/12 ML^2

14

For a uniform beam of length L and mass M, what is the moment of inertia through its end?

1/3 ML^2

15

What is the kinetic energy of a rotation object proportional to?

Moment of inertia about axis of rotation
Square of its angular speed

16

How can moment of inertia for a fly wheel be calculated?

Using 1/2 (Iω^2 + Mv^2) = Mgh

17

What is angular momentum?

Produce of moment of inertia and angular velocity

18

What is torque in relation to angular momentum?

Torque is rate of change of angular momentum

19

Define angular impulse

Change in angular momentum

20

Define conservation of angular momentum

I1ω1=I2ω2