Lecture 18: Exam Review 2

author: Walter H. G. Lewin, Center for Future Civic Media, Massachusetts Institute of Technology, MIT
recorded by: Massachusetts Institute of Technology, MIT
published: Oct. 10, 2008,   recorded: October 1999,   views: 17190
released under terms of: Creative Commons Attribution Non-Commercial Share Alike (CC-BY-NC-SA)

See Also:

Download Video - generic video source Download mit801f99_lewin_lec18_01.m4v (Video - generic video source 107.1 MB)

Download Video - generic video source Download mit801f99_lewin_lec18_01.rm (Video - generic video source 108.7 MB)

Download Video Download mit801f99_lewin_lec18_01.flv (Video 108.2 MB)

Download Video Download mit801f99_lewin_lec18_01_352x240_h264.mp4 (Video 149.2 MB)

Download Video Download mit801f99_lewin_lec18_01.wmv (Video 439.2 MB)

Download subtitles Download subtitles: TT/XML, RT, SRT

Help icon Streaming Video Help

Related Open Educational Resources

Related content

Report a problem or upload files

If you have found a problem with this lecture or would like to send us extra material, articles, exercises, etc., please use our ticket system to describe your request and upload the data.
Enter your e-mail into the 'Cc' field, and we will keep you updated with your request's status.
Lecture popularity: You need to login to cast your vote.



1. Work-Energy Theorem:

The conservation of mechanical energy applies when there are only conservative forces. The work-energy theorem always applies (also when non-conservative forces, such as friction, operate). A block on an inclined plane with friction is analyzed to solve for the coefficient of static friction. The work-energy theorem is shown to provide an elegant solution to solving for the block's velocity.

2. Bizarre Spinning Top - Part I:

A top is spun on the desk in the lecture hall to show that friction dissipates the top's kinetic energy into heat (the friction does negative work), and the top quickly falls over. Professor Lewin then spins the same top on a small magic black box. The top does not fall over, how bizarre!

3. Pendulum, Work and Energy:

A pendulum problem is discussed with a set of initial conditions. The maximum angular swing of the pendulum is calculated using the initial conditions and the conservation of mechanical energy. The work-energy theorem gives the same result. Numerical results are obtained for both the maximum angular swing and the phase angle.

4. Bizarre Spinning Top - Part II:

Fifteen minutes later the top is still spinning. How on Earth is this possible?

5. Spring, SHO and Initial Conditions:

Conservation of mechanical energy is used to calculate the maximum displacement of an object attached to a spring for given initial conditions.

6. Newton's Law of Universal Gravitation:

The orbital speed of the Earth around the sun is calculated. The kinetic and potential energies of the Earth are reviewed. The escape velocity, to leave the solar system is discussed.

7. Resistive Forces, Viscous Term:

This segment reviews concepts and measurements from lecture 12 such as the viscous and pressure drag terms, the terminal velocity, and the critical velocity.

8. Collisions and Conservation of Momentum:

In the absence of a net external force on a system, momentum of the system as a whole is conserved even when objects in the system collide and when kinetic energy is destroyed (a rather non-intuitive concept).

9. Bizarre Spinning Top - Part III:

The top has been spinning now for over 30 minutes; what's going on?

Link this page

Would you like to put a link to this lecture on your homepage?
Go ahead! Copy the HTML snippet !

Reviews and comments:

Comment1 Davor form VideoLectures, December 18, 2017 at 10:29 a.m.:

Hi all!

We have translated this entire course for you from English into 11 languages.

Check this video and give us some feedback in this short survey https://www.surveymonkey.co.uk/r/6DMBC3Q

Write your own review or comment:

make sure you have javascript enabled or clear this field: