Physics

1
Introduction to Vectors and Scalars
by Khan Academy 684,069 views
Learn more: http://www.khanacademy.org/video?v=ihNZlp7iUHE
Distance, displacement, speed and velocity. Difference between vectors and scalars 
2
Calculating Average Velocity or Speed
by Khan Academy 418,128 views
Learn more: http://www.khanacademy.org/video?v=oRKxmXwLvUU
Example of calculating speed and velocity 
3
Solving for Time
by Khan Academy 233,408 views
Learn more: http://www.khanacademy.org/video?v=awzOvyMKeMA
Simple example of solving for time given distance and rate 
4
Displacement from Time and Velocity Example
by Khan Academy 204,843 views
Learn more: http://www.khanacademy.org/video?v=lQdvt3V4yQ
Worked example of calculating displacement from time and velocity 
5
Acceleration
by Khan Academy 272,370 views
Learn more: http://www.khanacademy.org/video?v=FOkQszg1j8
Calculating the acceleration of a Porshe 
6
Newton's First Law of Motion
by Khan Academy 308,728 views
Learn more: http://www.khanacademy.org/video?v=CQYELiTtUs8
Newton's First Law (Galileo's Law of Inertia). 
7
Newton's Second Law of Motion
by Khan Academy 248,868 views
Learn more: http://www.khanacademy.org/video?v=ou9YMWlJgkE
Newton's Second Law of Motion: F=ma 
8
Newton's Third Law of Motion
by Khan Academy 193,709 views
Learn more: http://www.khanacademy.org/video?v=ByggTfeuJU
Every action has an equal and opposite reaction 
9
Airbus A380 Takeoff Time
by Khan Academy 142,324 views
Learn more: http://www.khanacademy.org/video?v=p4DTormtEG0
Figuring how long it takes an a380 to take off given a constant acceleration 
10
Airbus A380 Takeoff Distance
by Khan Academy 95,748 views
Learn more: http://www.khanacademy.org/video?v=fQt69_Q2CTw
How long of a runway does as a380 need 
11
Why Distance is Area under VelocityTime Line
by Khan Academy 127,631 views
Learn more: http://www.khanacademy.org/video?v=d_eqgj5K8
Understanding why distance is area under velocitytime line 
12
Average Velocity for Constant Acceleration
by Khan Academy 158,664 views
Learn more: http://www.khanacademy.org/video?v=MAS6mBRZZXA
Calculating average velocity when acceleration is constant 
13
Acceleration of Aircraft Carrier Takeoff
by Khan Academy 81,752 views
Learn more: http://www.khanacademy.org/video?v=VYgSXBjEA8I
Using what we know about takeoff velocity and runway length to determine acceleration 
14
Race Cars with Constant Speed Around Curve
by Khan Academy 73,624 views
Learn more: http://www.khanacademy.org/video?v=ITA1rW5UraU
When acceleration could involve a change in direction and not speed 
15
Introduction to Gravity
by Khan Academy 150,801 views
Learn more: http://www.khanacademy.org/video?v=Xcel427Ezl0
Basics of gravity and the Law of Universal Gravitation 
16
Mass and Weight Clarification
by Khan Academy 87,543 views
Learn more: http://www.khanacademy.org/video?v=IuBoeDihLUc
Difference between mass and weight 
17
Gravity for Astronauts in Orbit
by Khan Academy 74,020 views
Learn more: http://www.khanacademy.org/video?v=oIZVixRTcY
Why do astronauts appear weightless despite being near the Earth? 
18
Would a Brick or Feather Fall Faster
by Khan Academy 75,075 views
Learn more: http://www.khanacademy.org/video?v=36Rym2q4H94
What would fall faster on the moon? 
19
Deriving Displacement as a Function of Time, Acceleration and Initial Velocity
by Khan Academy 98,207 views
Learn more: http://www.khanacademy.org/video?v=wlB0x9WqBU
Deriving displacement as a function of time, constant acceleration and initial velocity 
20
Plotting Projectile Displacement, Acceleration, and Velocity
by Khan Academy 90,197 views
Learn more: http://www.khanacademy.org/video?v=T0zpF_j7Mvo
Plotting projectile displacement, acceleration, and velocity as a function to change in time 
21
Projectile Height Given Time
by Khan Academy 72,531 views
Learn more: http://www.khanacademy.org/video?v=IYS4Bd9F3LA
Figuring out how high a ball gets given how long it spends in the air 
22
Deriving Max Projectile Displacement Given Time
by Khan Academy 45,563 views
Learn more: http://www.khanacademy.org/video?v=P7LKEkcNibo
Deriving a formula for maximum projectile displacement as a function of elapsed time 
23
Impact Velocity From Given Height
by Khan Academy 53,569 views
Learn more: http://www.khanacademy.org/video?v=2ZgBJxT9pbU
Determining how fast something will be traveling upon impact when it is released from a given height 
24
Visualizing Vectors in 2 Dimensions
by Khan Academy 123,344 views
Learn more: http://www.khanacademy.org/video?v=xp6ibuI8UuQ
Visualizing, adding and breaking down vectors in 2 dimensions 
25
Projectile at an Angle
by Khan Academy 131,093 views
Learn more: http://www.khanacademy.org/video?v=ZZ39o1rAZWY
Figuring out the horizontal displacement for a projectile launched at an angle 
26
Different Way to Determine Time in Air
by Khan Academy 62,431 views
Learn more: http://www.khanacademy.org/video?v=_NWc3C3cTNA
Another way to determine time in the air given an initial vertical velocity 
27
Launching and Landing on Different Elevations
by Khan Academy 60,163 views
Learn more: http://www.khanacademy.org/video?v=a5QnXi_lZII
More complicated example involving launching and landing at different elevations 
28
Total Displacement for Projectile
by Khan Academy 51,237 views
Learn more: http://www.khanacademy.org/video?v=UXORCpvKYiI
Reconstructing the total displacement vector for a projectile 
29
Total Final Velocity for Projectile
by Khan Academy 40,792 views
Learn more: http://www.khanacademy.org/video?v=sTp4cI9VyCU
Calculating the total final velocity for a projectile landing at a different altitude (mistake near end: I write 29.03 when it should be 26.03 m/s and the final total magnitude should be 26.55 m/s 78.7 degrees below horizontal 
30
Correction to Total Final Velocity for Projectile
by Khan Academy 21,981 views
Learn more: http://www.khanacademy.org/video?v=DNoDJlB0ygU
Correction to "Total Final Velocity for Projectile" Video 
31
Projectile on an Incline
by Khan Academy 42,476 views
Learn more: http://www.khanacademy.org/video?v=jNESnky3RVg
Challenging problem of a projectile on an inclined plane 
32
Unit Vectors and Engineering Notation
by Khan Academy 36,512 views
Learn more: http://www.khanacademy.org/video?v=2QjdcVTgTTA
Using unit vectors to represent the components of a vector 
36
Optimal angle for a projectile part 2  Hangtime
by Khan Academy 31,567 views
Learn more: http://www.khanacademy.org/video?v=XtAB9GOfLiM
Optimal angle for a projectile part 2  Hangtime 
37
Optimal angle for a projectile part 3  Horizontal distance as a function of angle (and speed)
by Khan Academy 29,481 views
Learn more: http://www.khanacademy.org/video?v=h_x8TwC1ik
Horizontal distance as a function of angle (and speed) 
39
Normal Force and Contact Force
by Khan Academy 96,062 views
Learn more: http://www.khanacademy.org/video?v=1WOrgrIcQZU
The force that keeps a block of ice from falling towards the center of the earth 
40
Normal Force in an Elevator
by Khan Academy 87,034 views
Learn more: http://www.khanacademy.org/video?v=hoRsHNSrMpc
How the normal force changes when an elevator accelerates 
41
Inclined Plane Force Components
by Khan Academy 171,210 views
Learn more: http://www.khanacademy.org/video?v=TC23wD34C7k
Figuring out the components of the force due to gravity that are parallel and perpendicular to the surface of an inclined plane 
42
Ice Accelerating Down an Incline
by Khan Academy 80,019 views
Learn more: http://www.khanacademy.org/video?v=Mz2nDXElcoM
Figuring out the acceleration of ice down a plane made of ice 
43
Force of Friction Keeping the Block Stationary
by Khan Academy 103,974 views
Learn more: http://www.khanacademy.org/video?v=v8ODIMqbQ44
Block of wood kept stationary by the force of friction (Correction made in next video) 
44
Correction to Force of Friction Keeping the Block Stationary
by Khan Academy 43,331 views
Learn more: http://www.khanacademy.org/video?v=BukTc4q9BMc
Correction to Force of Friction Keeping the Block Stationary 
45
Force of Friction Keeping Velocity Constant
by Khan Academy 67,372 views
Learn more: http://www.khanacademy.org/video?v=iA7Thhnzc64
Calculating the coefficient of kinetic friction (correction made in next video) 
46
Intuition on Static and Kinetic Friction Comparisons
by Khan Academy 54,808 views
Learn more: http://www.khanacademy.org/video?v=J9BWNiOSGlc
Why static friction is harder to overcome than kinetic friction 
47
Static and Kinetic Friction Example
by Khan Academy 120,131 views
Learn more: http://www.khanacademy.org/video?v=ZA_D4O6l1lo
Thinking about the coefficients of static and kinetic friction 
48
Introduction to Tension
by Khan Academy 273,033 views
Learn more: http://www.khanacademy.org/video?v=_UrfHFEBIpU
An introduction to tension. Solving for the tension(s) in a set of wires when a weight is hanging from them. 
49
Tension (part 2)
by Khan Academy 160,473 views
Learn more: http://www.khanacademy.org/video?v=zwDJ1wVr7Is
A slightly more difficult tension problem. 
50
Tension in an accelerating system and pie in the face
by Khan Academy 106,864 views
Learn more: http://www.khanacademy.org/video?v=52wxpYnS64U
The second part to the complicated problem. We figure out the tension in the wire connecting the two masses. Then we figure our how much we need to accelerate a pie for it to safely reach a man's face. 
53
Introduction to Momentum
by Khan Academy 302,834 views
Learn more: http://www.khanacademy.org/video?v=XFhntPxow0U
What momentum is. A simple problem involving momentum. 
54
Momentum: Ice skater throws a ball
by Khan Academy 150,732 views
Learn more: http://www.khanacademy.org/video?v=vPkkCOlGND4
A simple conservation of momentum problem involving an ice skater and a ball 
55
2dimensional momentum problem
by Khan Academy 154,801 views
Learn more: http://www.khanacademy.org/video?v=CFygKiTB4A
An example of conservation of momentum in two dimensions. 
56
2dimensional momentum problem (part 2)
by Khan Academy 76,877 views
Learn more: http://www.khanacademy.org/video?v=leudxqivIJI
We finish the 2dimensional momentum problem 
57
Introduction to work and energy
by Khan Academy 375,352 views
Learn more: http://www.khanacademy.org/video?v=2WS1sG9fhOk
Introduction to work and energy 
58
Work and Energy (part 2)
by Khan Academy 227,447 views
Learn more: http://www.khanacademy.org/video?v=3mier94pbnU
More on work. Introduction to Kinetic and Potential Energies. 
59
Conservation of Energy
by Khan Academy 250,543 views
Learn more: http://www.khanacademy.org/video?v=kw_4Loo1HR4
Using the law of conservation of energy to see how potential energy is converted into kinetic energy 
60
Work/Energy problem with Friction
by Khan Academy 182,096 views
Learn more: http://www.khanacademy.org/video?v=YvacYWgygaA
A conservation of energy problem where all of the energy is not conserved. 
61
Introduction to mechanical advantage
by Khan Academy 106,404 views
Learn more: http://www.khanacademy.org/video?v=pfzJz5Ij48
Introduction to simple machines, mechanical advantage and moments. 
62
Mechanical Advantage (part 2)
by Khan Academy 55,158 views
Learn more: http://www.khanacademy.org/video?v=DiBXxWBrV24
More on mechanical advantage, levers and moments. 
63
Mechanical Advantage (part 3)
by Khan Academy 162,961 views
Learn more: http://www.khanacademy.org/video?v=vSsK7Rfa3yA
Introduction to pulleys and wedges 
64
Center of Mass
by Khan Academy 212,936 views
Learn more: http://www.khanacademy.org/video?v=VrflZifKIuw
Introduction to the center of mass 
65
Introduction to Torque
by Khan Academy 303,049 views
Learn more: http://www.khanacademy.org/video?v=QhuJn8YBtmg
An introduction to torque 
66
Moments
by Khan Academy 231,540 views
Learn more: http://www.khanacademy.org/video?v=ESusD8HRLBI
Introduction to moments 
67
Moments (part 2)
by Khan Academy 104,486 views
Learn more: http://www.khanacademy.org/video?v=peXbz0frV74
2 more moment problems. 
68
Unit Vector Notation
by Khan Academy 118,793 views
Learn more: http://www.khanacademy.org/video?v=FaF3vezbSk
Expressing a vector as the scaled sum of unit vectors 
69
Unit Vector Notation (part 2)
by Khan Academy 45,520 views
Learn more: http://www.khanacademy.org/video?v=595Tiga1gIg
More on unit vector notation. Showing that adding the x and y components of two vectors is equivalent to adding the vectors visually using the headtotail method 
72
Projectile Motion with Ordered Set Notation
by Khan Academy 23,029 views
Learn more: http://www.khanacademy.org/video?v=jl_gQeL3xo
Solving the second part to the projectile motion problem (with wind gust) using ordered set vector notation 
73
Centripetal Force and Acceleration Intuition
by Khan Academy 96,002 views
Learn more: http://www.khanacademy.org/video?v=vZOk8NnjILg
The direction of the force in cases of circular motion at constant speeds 
74
Visual Understanding of Centripetal Acceleration Formula
by Khan Academy 58,329 views
Learn more: http://www.khanacademy.org/video?v=NH1_sO8QY3o
Visual understanding of how centripetal acceleration relates to velocity and radius 
75
Relationship between angular velocity and speed
by Khan Academy 143,425 views
Learn more: http://www.khanacademy.org/video?v=zAx61CO5mDw
How angular velocity relates to speed 
76
Calculus proof of centripetal acceleration formula
by Khan Academy 31,619 views
Learn more: http://www.khanacademy.org/video?v=XjCEumlJBno
Proving that a = v^2/r 
77
Loop De Loop Question
by Khan Academy 37,974 views
Learn more: http://www.khanacademy.org/video?v=wjZb3zPuoeA
Asks students to find the minimum speed necessary to complete the loop de loop 
78
Loop De Loop Answer part 1
by Khan Academy 34,987 views
Learn more: http://www.khanacademy.org/video?v=4SQDybFjhRE
Figuring out the minimum speed at the top of the loop de loop to stay on the track 
79
Loop De Loop Answer part 2
by Khan Academy 23,171 views
Learn more: http://www.khanacademy.org/video?v=zcnnZz2pCSg
Figuring out the car's average speed while completing the loop de loop 
80
Acceleration Due to Gravity at the Space Station
by Khan Academy 30,074 views
Learn more: http://www.khanacademy.org/video?v=R5CRZONOHCU
What is the acceleration due to gravity at the space station 
81
Space Station Speed in Orbit
by Khan Academy 27,105 views
Learn more: http://www.khanacademy.org/video?v=9BNkmfHYYYI
Speed necessary for the space station to stay in orbit 
82
Conservation of angular momemtum
by Khan Academy 126,428 views
Learn more: http://www.khanacademy.org/video?v=s_R8d3isJDA
Angular momentum is constant when there is no net torque. 
83
Introduction to Newton's Law of Gravitation
by Khan Academy 142,412 views
Learn more: http://www.khanacademy.org/video?v=391txUI76gM
A little bit on gravity 
84
Gravitation (part 2)
by Khan Academy 75,454 views
Learn more: http://www.khanacademy.org/video?v=8i0j3j16yFk
A little bit more on gravity 
85
Intro to springs and Hooke's Law
by Khan Academy 164,489 views
Learn more: http://www.khanacademy.org/video?v=ZzwuHS9ldbY
Introduction to Hooke's Law 
86
Potential energy stored in a spring
by Khan Academy 108,035 views
Learn more: http://www.khanacademy.org/video?v=eVl5zs6Lqy0
Work needed to compress a spring is the same thing as the potential energy stored in the compressed spring. 
87
Spring potential energy example (mistake in math)
by Khan Academy 57,753 views
Learn more: http://www.khanacademy.org/video?v=P3QV9ktuYlQ
A spring, a frozen loopdloop and more! (See if you can find the mistake I made and get the right answer!) 
88
Introduction to Harmonic Motion
by Khan Academy 189,656 views
Learn more: http://www.khanacademy.org/video?v=Nk2q_jkJVs
Intuition behind the motion of a mass on a spring (some calculus near the end). 
89
Harmonic Motion Part 2 (calculus)
by Khan Academy 105,952 views
Learn more: http://www.khanacademy.org/video?v=xoUppFlif04
We test whether Acos(wt) can describe the motion of the mass on a spring by substituting into the differential equation F=kx 
90
Harmonic Motion Part 3 (no calculus)
by Khan Academy 85,315 views
Learn more: http://www.khanacademy.org/video?v=oqBHBO8cqLI
Figuring out the period, frequency, and amplitude of the harmonic motion of a mass attached to a spring. 
91
Fluids (part 1)
by Khan Academy 261,667 views
Learn more: http://www.khanacademy.org/video?v=Pn5YEMwQb4Y
What a fluid is. Difference between liquids and gasses (both fluids). 
92
Fluids (part 2)
by Khan Academy 139,371 views
Learn more: http://www.khanacademy.org/video?v=lWDtFHDVqqk
Pressure and Pascal's Principal. 
93
Fluids (part 3)
by Khan Academy 105,946 views
Learn more: http://www.khanacademy.org/video?v=5EWjlpc0S00
Pressure in a fluid at depth 
94
Fluids (part 4)
by Khan Academy 82,526 views
Learn more: http://www.khanacademy.org/video?v=i6gz9VFyYks
Using our understanding of fluid pressure to figure out the height of a column of mercury. 
95
Fluids (part 5)
by Khan Academy 87,558 views
Learn more: http://www.khanacademy.org/video?v=vzID7ds600c
Introduction to Archimedes' principle and buoyant force. 
96
Fluids (part 6)
by Khan Academy 76,130 views
Learn more: http://www.khanacademy.org/video?v=wwjtuZ5vTvc
A couple of problems involving Archimedes' principle and buoyant forces. 
97
Fluids (part 7)
by Khan Academy 71,585 views
Learn more: http://www.khanacademy.org/video?v=G4CgOF4ccXk
Introduction to the study of moving fluids. 
98
Fluids (part 8)
by Khan Academy 64,836 views
Learn more: http://www.khanacademy.org/video?v=uqyLOuAzbvo
Beginning of the proof of Bernoulli's Equation. 
99
Fluids (part 9)
by Khan Academy 53,741 views
Learn more: http://www.khanacademy.org/video?v=QX2YLR09Q78
Second part of the Bernoulli's Equation proof. Beginning of a problem that uses the equation. 
100
Fluids (part 10)
by Khan Academy 46,791 views
Learn more: http://www.khanacademy.org/video?v=NGpJPz44JYc
Second part of the example that uses Bernoulli's equation. 
101
Fluids (part 11)
by Khan Academy 38,422 views
Learn more: http://www.khanacademy.org/video?v=HnfBFeLunk4
Clarification of the problem in part 10 
102
Fluids (part 12)
by Khan Academy 50,449 views
Learn more: http://www.khanacademy.org/video?v=xlJYYM5TWoA
Complete example of a Bernoulli's Equation exercise. 
103
Thermodynamics (part 1)
by Khan Academy 450,718 views
Learn more: http://www.khanacademy.org/video?v=tQcB9BLUoVI
Intuition of how gases generate pressure in a container and why pressure x volume is proportional to the combined kinetic energy of the molecules in the volume. 
104
Thermodynamics (part 2)
by Khan Academy 169,602 views
Learn more: http://www.khanacademy.org/video?v=x34OTtDE5q8
Example problem that pv=pv. Introduction to temperature. 
105
Thermodynamics (part 3)
by Khan Academy 118,498 views
Learn more: http://www.khanacademy.org/video?v=HvYUKRMT0VI
Introduction to Kelvin. Example of a problem involving the ideal gas law 
106
Thermodynamics (part 4)
by Khan Academy 91,916 views
Learn more: http://www.khanacademy.org/video?v=5B1i26dUwME
Introduction to the concept of a mole. Universal gas constant R. PV=nRT 
107
Thermodynamics (part 5)
by Khan Academy 90,012 views
Learn more: http://www.khanacademy.org/video?v=UekR9J31a2o
Example problem involving PV=nRT 
108
Electrostatics (part 1): Introduction to Charge and Coulomb's Law
by Khan Academy 406,449 views
Learn more: http://www.khanacademy.org/video?v=NXMgvrS8Gr8
Introduction to Charge and Coulomb's Law (video from May 2008 that I forgot to upload) 
109
Electrostatics (part 2)
by Khan Academy 243,911 views
Learn more: http://www.khanacademy.org/video?v=0YOGrTNgGhE
Electric Fields 
110
Proof (Advanced): Field from infinite plate (part 1)
by Khan Academy 116,528 views
Learn more: http://www.khanacademy.org/video?v=prLfVucoxpw
Electric field generated by a uniformly charged, infinite plate 
111
Proof (Advanced): Field from infinite plate (part 2)
by Khan Academy 54,703 views
Learn more: http://www.khanacademy.org/video?v=TxwE4_dXo8s
We see that the infinite, uniformly charged plate generates a constant electric field (independent of the height above the plate) 
112
Electric Potential Energy
by Khan Academy 287,840 views
Learn more: http://www.khanacademy.org/video?v=elJUghWSVh4
Introduction to electric potential 
113
Electric Potential Energy (part 2 involves calculus)
by Khan Academy 131,381 views
Learn more: http://www.khanacademy.org/video?v=CqsYCIjSm9A
Electric potential energy difference in a varying field 
114
Voltage
by Khan Academy 226,975 views
Learn more: http://www.khanacademy.org/video?v=zqGvUbvVQXg
Difference between electrical potential (voltage) and electrical potential energy 
115
Capacitance
by Khan Academy 226,658 views
Learn more: http://www.khanacademy.org/video?v=ngOC4eUQl8Y
Introduction to the capacitance of a two place capacitor 
116
Circuits (part 1)
by Khan Academy 416,576 views
Learn more: http://www.khanacademy.org/video?v=3o8_EARoMtg
Introduction to electricity, circuits, current and resistance 
117
Circuits (part 2)
by Khan Academy 213,708 views
Learn more: http://www.khanacademy.org/video?v=7vHh1sfZ5KE
Resistors in series 
118
Circuits (part 3)
by Khan Academy 183,813 views
Learn more: http://www.khanacademy.org/video?v=ZrMw7P6P2Gw
Resistors in parallel 
119
Circuits (part 4)
by Khan Academy 166,608 views
Learn more: http://www.khanacademy.org/video?v=3NcIK0s3IwU
A hairy resistance problem 
120
Cross product 1
by Khan Academy 128,460 views
Learn more: http://www.khanacademy.org/video?v=zA0fvwtvgvA
Introduction to the cross product 
121
Cross Product 2
by Khan Academy 64,986 views
Learn more: http://www.khanacademy.org/video?v=o_puKe_lTKk
A little more intuition on the cross product. 
122
Cross Product and Torque
by Khan Academy 77,700 views
Learn more: http://www.khanacademy.org/video?v=s38l6nmTrvM
The cross product and the direction of torque. 
123
Introduction to Magnetism
by Khan Academy 332,341 views
Learn more: http://www.khanacademy.org/video?v=8Y4JSp5U82I
An introduction to magnetism 
124
Magnetism 2
by Khan Academy 197,296 views
Learn more: http://www.khanacademy.org/video?v=NnlAI4ZiUrQ
Magnetic fields and their effects on moving electrical charges 
125
Magnetism 3
by Khan Academy 134,474 views
Learn more: http://www.khanacademy.org/video?v=LTuGQy4rmmo
Whats happens when a speeding proton goes through a magnetic field 
126
Magnetism 4
by Khan Academy 102,815 views
Learn more: http://www.khanacademy.org/video?v=b1QFKLZC11U
Part 2 of the proton through a magnetic field problem 
127
Magnetism 5
by Khan Academy 98,315 views
Learn more: http://www.khanacademy.org/video?v=jQ2nD8ZGeEw
Magnetic force on a wire carrying current. 
128
Magnetism 6: Magnetic field due to current
by Khan Academy 147,889 views
Learn more: http://www.khanacademy.org/video?v=Ri557hvwhcM
See how a wire carrying a current creates a magnetic field. 
129
Magnetism 7
by Khan Academy 86,993 views
Learn more: http://www.khanacademy.org/video?v=l3hw0twZSCc
The magnetic force that two currentcarrying wires exert on each other. 
130
Magnetism 8
by Khan Academy 70,574 views
Learn more: http://www.khanacademy.org/video?v=4tctB1wZNiI
More on the forces exerted by 2 current carrying wires on each other. 
131
Magnetism 9: Electric Motors
by Khan Academy 96,785 views
Learn more: http://www.khanacademy.org/video?v=pAgPfr7MkkU
Using a magnetic field to exert torque on a rotating circuit. 
132
Magnetism 10: Electric Motors
by Khan Academy 54,075 views
Learn more: http://www.khanacademy.org/video?v=cePkWyXRvIQ
Why the circuit will keep flipping over. 
133
Magnetism 11: Electric Motors
by Khan Academy 49,762 views
Learn more: http://www.khanacademy.org/video?v=XMkUDyl1ZRo
Using a commutator to solve the flipping problem and create an electric motor. 
134
Magnetism 12: Induced Current in a Wire
by Khan Academy 116,421 views
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Induced current and EMF in a moving wire from a magnetic field. 
135
The dot product
by Khan Academy 132,696 views
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Introduction to the vector dot product. 
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Dot vs. Cross Product
by Khan Academy 114,816 views
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Understanding the differences between the dot and cross products 
137
Calculating dot and cross products with unit vector notation
by Khan Academy 80,881 views
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Calculating the dot and cross products when vectors are presented in their x, y, and z (or i,j, and k) components. 
138
Introduction to Waves
by Khan Academy 215,694 views
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Introduction to transverse and longitudinal waves 
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Amplitude, Period, Frequency and Wavelength of Periodic Waves
by Khan Academy 226,253 views
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Amplitude, period, frequency and wavelength of periodic waves 
140
Introduction to the Doppler Effect
by Khan Academy 112,749 views
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Introduction to the Doppler Effect 
141
Doppler effect formula for observed frequency
by Khan Academy 51,842 views
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Doppler effect formula for observed frequency 
142
Doppler effect formula when source is moving away
by Khan Academy 45,828 views
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Doppler effect formula when source is moving away 
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When the source and the wave move at the same velocity
by Khan Academy 30,588 views
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When the source and the wave move at the same velocity 
144
Mach Numbers
by Khan Academy 29,159 views
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Mach numbers 
145
Specular and Diffuse Reflection
by Khan Academy 56,953 views
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Specular and Diffuse Reflection 
146
Specular and Diffuse Reflection 2
by Khan Academy 33,164 views
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Specular and Diffuse Reflection 2 
147
Refraction and Snell's Law
by Khan Academy 112,045 views
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Refraction and Snell's Law 
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Refraction in Water
by Khan Academy 58,471 views
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Refraction in Water 
149
Snell's Law Examples 1
by Khan Academy 63,000 views
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Snell's Law Examples 1 
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Snell's Law Example 2
by Khan Academy 34,398 views
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Snell's Law Example 2 
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Total Internal Reflection
by Khan Academy 77,327 views
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Critical incident angle and total internal reflection 
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Virtual Image
by Khan Academy 75,212 views
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Virtual Image 
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Parabolic Mirrors and Real Images
by Khan Academy 60,509 views
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Parabolic Mirrors and Real Images 
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Parabolic Mirrors 2
by Khan Academy 39,266 views
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Parabolic Mirrors 2 
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Convex Parabolic Mirrors
by Khan Academy 42,515 views
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Convex Parabolic Mirrors 
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Convex Lenses
by Khan Academy 82,846 views
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Convex Lenses 
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Convex Lens Examples
by Khan Academy 53,173 views
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Convex Lens Examples 
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Concave Lenses
by Khan Academy 57,254 views
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Concave Lenses 
159
Object Image and Focal Distance Relationship (Proof of Formula)
by Khan Academy 43,067 views
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Object Image and Focal Distance Relationship (Proof of Formula) 
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Object Image Height and Distance Relationship
by Khan Academy 29,965 views
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Object Image Height and Distance Relationship 
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Viewing g as the value of Earth's Gravitational Field Near the Surface
by Khan Academy 28,840 views
Learn more: http://www.khanacademy.org/video?v=1E3Z_R5AHdg
Viewing g as the value of Earth's gravitational field near the surface rather than the acceleration due to gravity near Earth's surface for an object in freefall