# Newton's Laws of Motion

## Static Equilibrium (First Law)

#### Rope Walker

RealVideo®
4:35 minutes (43:30 - 48:05)

Discussion of stability of rope walker with objects suspended to lower center of mass; brief demonstration of rope walker on zip line.

Instructor: Prof. Walter Lewin
Prior Knowledge: Equilibrium and Center of Mass (33:54 of V25)

## Dynamics of A Single Particle (Second Law)

#### Weightlessness During Free-Fall

RealVideo®
4:16 minutes (26:53 - 31:09)

Demonstration that a gallon of water (as well as Professor Lewin) is weightless while in free-fall during a jump off a table. Includes slow motion video of this demonstration.

Instructor: Prof. Walter Lewin
Prior Knowledge: Free-Fall (Beginning of V7)

#### Weightless Mass in Free-Fall

RealVideo®
8:19 minutes (31:09 - 39:28)

Demonstration, using a custom-made scale, that a barbell is weightless while in free-fall, then very heavy on impact with the ground.

Instructor: Prof. Walter Lewin
Prior Knowledge: Weightlessness During Free-Fall (26:53 of V7)

#### Waterplaning and Air Tracks

RealVideo®
5:19 minutes (36:22 - 41:41)

Explanation of how friction can be eliminated by hydroplaning and air tracks, with brief demonstrations.

Instructor: Prof. Walter Lewin
Prior Knowledge: Static Friction (Beginning of V8)

#### Weightlessness Video

RealVideo®
10:32 minutes (39:28 - 50:00)

Video demonstration of the Vomit Comet and explanation of its cycle and conditions.

Instructor: Prof. Walter Lewin
Prior Knowledge: Weightlessness During Free-Fall (26:53 of V7)

#### Measuring Static Friction

RealVideo®
4:37 minutes (7:01 - 11:38)

Demonstration using a wooden ramp of the dependence of μs on surface, but not surface area or mass.

Instructor: Prof. Walter Lewin
Prior Knowledge: Static Friction (Beginning of V8)

#### Pulley/Plane Demo

RealVideo®
5:53 minutes (30:29 - 36:22)

Demonstration of pulley/plane system; additional mass hangs, then falls; explanation of changing friction.

Instructor: Prof. Walter Lewin
Prior Knowledge: Example of Pulley/Plane System (20:50 of V8)

#### CO2 Shuttle

RealVideo®
6:26 minutes (41:41 - 48:07)

Video of a device that travels on cushion of CO2 on plate glass; the friction is so low a flea can pull a large book on the device.

Instructor: Prof. Walter Lewin
Prior Knowledge: Static Friction (Beginning of V8)

#### Yardstick Puzzle

RealVideo®
1:53 minutes (48:13 - 50:06)

Moving two fingers towards each other under a yardstick causes alternating movement.

Instructor: Prof. Walter Lewin
Prior Knowledge: Static Friction (Beginning of V8)

## Systems of Two or More Bodies (Third Law)

#### Hero's Engine(8.01 Fall 1999)

RealVideo®
4:14 minutes (22:10 - 26:24)

Newton's third law is demonstrated through a spinning engine propelled by steam.

Instructor: Prof. Walter Lewin
Prior Knowledge: Newton's Third Law (11:04 of V6)

#### Weightlessness During Free-Fall

RealVideo®
4:16 minutes (26:53 - 31:09)

Demonstration that a gallon of water (as well as Professor Lewin) is weightless while in free-fall during a jump off a table. Includes slow motion video of this demonstration.

Instructor: Prof. Walter Lewin
Prior Knowledge: Free-Fall (Beginning of V7)

#### Weightless Mass in Free-Fall

RealVideo®
8:19 minutes (31:09 - 39:28)

Demonstration, using a custom-made scale, that a barbell is weightless while in free-fall, then very heavy on impact with the ground.

Instructor: Prof. Walter Lewin
Prior Knowledge: Weightlessness During Free-Fall (26:53 of V7)

#### Measuring Static Friction

RealVideo®
4:37 minutes (7:01 - 11:38)

Demonstration using a wooden ramp of the dependence of μ_s on surface, but not surface area or mass.

Instructor: Prof. Walter Lewin
Prior Knowledge: Static Friction (Beginning of V8)

#### Pulley/Plane Demo

RealVideo®
5:53 minutes (30:29 - 36:22)

Demonstration of pulley/plane system; additional mass hangs, then falls; explanation of changing friction.

Instructor: Prof. Walter Lewin
Prior Knowledge: Example of Pulley/Plane System (20:50 of V8)