Marcel and I worked on a problem which we had started in the last session dealing with an inelastic collision. I then instructed him to do another problem in inelastic collisions which he did. After that, I explained how kinetic energy is not conserved in inelastic collisions because some energy is lost to heat. I proceeded to explain the difference between elastic collisions and inelastic collisions and worked one elastic collision for Marcel. There was no assignment.

Early theories of how light was transmitted were briefly discussed, these included corpuscular theory and streamer theory. The more modern dual theory was touched on, with light acting at times like a particle and at other times like a wave. A demonstration was used to show that an electric field produced a magnetic field, and that a magnetic field produced an electric field. Light was defined as an electro-magnetic wave, one in which each field generated the other, which propelled the wave, without a medium needed. A sketch of an electro-magnetic wave showed both phases and direction of motion.

A quiz on sound was utilized to evaluate the extent of learning of the subject matter dealing with sound and its transmission. The questions were answered and discussed immediately following the answering, so that it served as a learning procedure and not an evaluation procedure. This allowed me to complete this section, and begin the unit on light as our next meeting.

A discussion and demonstration of natural frequency, forced vibrations, resonance, and beats was presented using tuning forks.

Test given on sound waves,frequency of sound,wavelength, resonance, forced vibrations, natural frequency, and beats.
A discussion about the speed of light followed the test.

Marcel worked under my supervision to solve a problem involving the conservation of momentum. He had to realize that a system can start or end in zero total momentum even when objects are moving. He was able to recognize how both sides of a conservation of momentum equation are equal to zero with the initial conditions having no moving objects and the final conditions involved two moving objects. I then asked him to solve a thought experiment involving a person walking on a raft in still water. I finished the class by explaining the difference between elastic and inelastic collisions. There was no assignment.

I reviewed with Marcel about impulse, the product of force and time. I showed him a sample problem and instructed him to do a problem using the formula for impulse. I also demonstrated the use of the concept of impulse using a different version of the formula for impulse for another problem. There was no assignment.

The early theories of light were presented as being particles which passed from eye to object, and the opposing theory as particles passing from object to eye. The particle and wave theory of light was briefly discussed, along with the dual nature theory, light acting like particles at times, and like waves at other times. A changing electric current was shown to produce a magnetic field, and a changing magnetic field was shown to produce an electric current. The principle that light was an electromagnetic wave, which propagated itself by producing both a magnetic and electric part to the wave was presented using diagrams. That the electromagnetic wave could self propagate was used to explain why a medium is not needed for transmission.

I defined momentum for Marcel as the product of mass and the velocity vector so that he understood that momentum is a vector and requires direction. We did a problem to solve for velocity when momentum was known. I then defined impulse and the formula that equated impulse with the change in momentum. I showed Marcel the deformation of golf balls and baseballs in a video with high speed capabilities. I went over a sample problem in impulse with Marcel. There was no assignment.

A question and answer session was undertaken to better determine the scope of the subject dealing with waves and sound Bobby had covered, and was able to explain. A series of written questions was used, and we discussed the answers and how to best arrive at the correct answer. The effect of frequency on the pitch of a sound was demonstrated with a series of tuning forks, as well as using the wave formula to determine the effect of frequency on wave length.