Flashcards in Physics Definitions and Equations Deck (93):

1

## Acceleration

### How much an object's speed changes in one second

2

## Kinematics Equations (4)

###
Vf = Vo+at

x = Vot+1/2at^2

Vf^2 = Vo^2+2ax

x = 1/2t(Vo+Vf)

3

## Angular Momentum (Extended object) Equation

### L = Iw

4

## Angular Momentum (Point object) Equation

### L = mrv

5

## Impulse- Momentum Theorem Equation

###
torque(time)= L

(Change in angular momentum equals the net torque multiplied by the time the torque is applied)

6

## Displacement

### How far an object ends up from its initial position

7

## Average Velocity

### Displacement divided by the time interval over which that displacement occurred

8

## Instantaneous Velocity

### How fast an object is moving at a specific moment in time

9

## How to determine how far from the detector an object is located (Position-time graph)?

### Look at the vertical axis of the position-time graph

10

## How to determine how fast an object is moving (Position-time graph)?

### Look at the steepness/slope of the position-time graph

11

## How to determine which way the object is moving (Position-time graph)?

### Look at which way the position-time graph is sloped

12

## How to determine how fast an object is moving (Velocity-time graph)?

### Look at the vertical axis of the velocity-time graph

13

## How to determine which way the object is moving (Velocity-time graph)?

### Look at whether the velocity-time graph is above or below the horizontal axis

14

## How to determine how far an object travels (Velocity-time graph)?

### Determine the area between the velocity-time graph and the horizontal axis

15

## When an object is in free-fall...

###
Vertical acceleration is always 10 m/s

Horizontal acceleration is always zero

16

## Angular Displacement (Theta)

### The angle through which an object has rotated (radians)

17

## Average Angular Velocity (w)

### Angular displacement divided by the time interval over which that angular displacement occurred (rad/s)

18

## Instantaneous Angular Velocity

### How fast an object is rotating at a specific moment in time

19

## Angular Acceleration (fishy a)

### How much an object's angular speed changes in one second (rad/s^2)

20

## Difference between angular acceleration and centripetal acceleration?

###
Angular acceleration changes an object's rotational speed.

Centripetal acceleration changes an object's direction of motion.

21

## Linear Displacement (Rotating object) Equation

### x = r(theta)

22

## Linear Speed (Rotating object) Equation

### v = rw

23

## Linear Acceleration (Rotating object) Equation

### a = r(fishy a)

24

## Torque Equation

### torque = Fd

25

## Rotational Inertia (I)

### Resistance to angular acceleration

26

## Rotational Inertia (Point particle) Equation

### I = MR^2

27

## Angular Acceleration Equation

### fishy a = net torque / I

28

## Mechanical energy is conserved when?

### No net work done by external forces

29

## Angular momentum is conserved when?

### No net external torque acts

30

## Momentum in a direction is conserved when?

### No net external force acts in that direction

31

## Momentum Equation

###
p = mv

(mass times velocity)

Units: Newton seconds

32

## Impulse Equation

###
J = change in momentum

J = Ft

Units: Newton seconds

33

## What is impulse in a force-time graph?

### The area

34

## Crest

### High points on a wave

35

## Trough

### Low points on a wave

36

## Amplitude (A)

### The distance from the midpoint to the crest or trough

37

## Wavelength (lambda)

### The distance between identical parts of the wave

38

## Frequency (f)

###
The number of waves to pass a position in one second

Units: Hertz (Hz)

39

## Period (T)

### The time for one wavelength to pass a position

40

## Frequency Equation

### f = 1/T

41

## Period Equation

### T = 1/f

42

## Speed of a Wave Equations (2)

###
v = lambda(f)

v = lambda/T

43

## Transverse Wave

### Motion of a material is at right angles to the direction in which the wave travels

44

## Longitudinal Waves

### A material vibrates parallel to the direction of the wave

45

## Interference

### Waves arrive at the same point at the same time

46

## Constructive Interference

###
Crest of one wave overlaps the crest of another.

Result: Wave of increased amplitude

47

## Destructive Interference

###
Crest of one wave overlaps the trough of another

Result: Wave of reduced amplitude

48

## Superposition

### Where the wave pulses overlap, the resulting displacement can be determined by adding the displacements of the two pulses

49

## Beats

### When two waves of slightly different frequency interfere. Beat frequency is the difference between the frequencies of the two waves

50

## Doppler Effect

###
Change in frequency due to motion of the source.

Wave source approaches...waves with higher frequency

Wave source moves away...waves with a lower frequency

51

## What does the pitch of a sound depend on?

### Sound wave's frequency

52

## What does the loudness of a sound depend on?

### Sound wave's amplitude

53

## What does the energy carried by a sound wave depend on?

### Wave's amplitude

54

## Standing Wave

### Wave that appears to stay in one place

55

## Nodes

### Stationary points on a standing wave

56

## Antinodes

### Positions on a standing waves with the largest amplitudes

57

## Fundamental

### The lowest frequency standing wave

58

## How is wavelength measured on a standing wave?

### Node to node

59

## What is the fundamental frequency for a standing wave with identical boundaries?

###
v/2L

Harmonies exist in all multiples of the fundamental

60

## What is the fundamental frequency for a standing wave with different boundaries?

###
v/4L

Harmonies exist only in odd multiples of the fundamental

61

## Object in Equilibrium

### The object moves in a straight line at constant speed. The net force is zero.

62

## Force

### Push or pull that acts on an object. It is always in the direction of acceleration.

63

## Force Equation

###
F = ma

Units: Newtons

64

## Equilibrium Force Equations

###
(up force)-(down force) = 0

(left force)-(right force) = 0

65

## Mass

### Tells how much material is contained in an object

66

## Weight

### Force of a planet acting on an object

67

## Normal force

### Force of a surface on an object in contact with that surface. It acts perpendicular to the surface.

68

## What is the resultant force when two concurrent forces act perpendicular to one another?

### Greater than if the forces acted in opposite directions, but less than if the forces acted in the same direction.

69

## What is the horizontal and vertical component of a force when the angle of the diagonal force is measured from the horizontal?

###
Horizontal component is the magnitude of the force times cos(theta)

Vertical component is the magnitude of the force times sin(theta)

70

## Force of Friction

### Force of a surface on an object acting along the surface

71

## Force of Friction Equation

###
Ff = uFn

(Force of friction equals the coefficient of friction times the normal force)

72

## Difference between kinetic friction and static friction?

###
Kinetic friction is used when an object is moving. Static friction is used when an object is not moving.

Maximum coefficient of static friction is greater than the coefficient of kinetic friction.

73

## Newton's LUG

### All massive objects attract each other with a gravitational force

74

## Gravitational force (Fg) Equation

### Fg = G (M1M2)/d^2

75

## Gravitational Field (g) Equation

### g = GM/d^2

76

## Weight (aka gravitational mass) Equation

###
weight = mg

(gravitational mass is equal to inertial mass)

77

## Inertial Mass Equation

###
F = ma

(inertial mass is equal to gravitational mass)

78

## Component of the Object's Weight (Parallel to incline) Equation

### mg(sin(theta))

79

## Component of the Object's Weight (Perpendicular to incline) Equation

### mg(cos(theta))

80

## Newton's Third Law

### Force of object A on object B is equal to the force of object B on object A

81

## Circular Motion Acceleration Equation

### v^2/r directed towards the center of the circle

82

## Work Equation

###
W = Fx

(force multiplied by the distance an object moves parallel to that force)

83

## What is work in a force-displacement graph?

### The area

84

## What are the units for energy?

### Joules (J)

85

## Kinetic Energy Equation

### KE = 1/2mv^2

86

## gravitational Potential Energy Equation

### PE = mgh

87

## Mechanical Energy Equation

### KE+PE = ME

88

## Spring Potential Energy Equation

### PE (spring) = 1/2kx^2

89

## Rotational Kinetic Energy

### KE (rotational) = 1/2Iw^2

90

## Work- Energy Theorem Equation

### W (external) = (KEf-KEi) + (PEf-PEi)

91

## Force of a Spring Equation

###
F = kx

Units: Newton/meters

92

## Power Equation

###
p = work/time

p = Force(velocity)

(amount of work done in one second)

93