Marcel worked the entire session on test problems including addition of perpendicular vectors, navigation, and projectile motion at an angle. His score, including bonus points, added up to 124%. Solving these problems required the use of kinematic formulas and trigonometry. There was no assignment.

A quick review of the types of mechanical energy discussed last week was used to begin the class. Elastic, Chemical, and Gravitational Potential energy were reviewed, along with the formulas. That gravitational PE was determined by the force and distance moved against gravity and not the route used was demonstrated with diagrams. The formula for kinetic energy (KE) was given, and that the work done by an object is equal to the KE, so that W=KE, or expanded to fd=1/2mv2. The statement was shown; "when work is done, energy changes".

The plan was to continue standing by with Marcel while he completed his test. The test was not finished due to his participation in a School Wide Activity. There was no assignment.

The description of the 3 forms of mechanical energy was reviewed, with the emphasis on the gravitational potential energy. Using diagrams and a demonstration utilizing a board at different angles, the fact that the GPE remains the same regardless of the route used to reach a height. The formula PE=mgh was listed and a few problems to be solved. Kinetic energy defined as energy of motion was shown to be equal to 1/2 mass x velocity squared . KE is equal to the work done, so that work=KE or fd=1/2mv2.

Marcel used his practice test as a reference and started on his real test. Problems included resultant vectors from two perpendicular vectors, adding velocity vectors algebraically, and calculating horizontal and vertical distances in projectile motion. He did not complete his test yet. There was no assignment.

Class started with a check of answers to homework questions.Demonstrations of stretched rubber bands, textbooks lifted and dropped on pretzels, and clocks wound by hand were used to show that work was done and in each example, the band, book and spring had the ability to do work. This ability is called energy and measured in joules. The concentration of the lesson was on mechanical energy, the energy of position. The first form of ME was defined as potential energy (PE), which is "stored energy". The examples being elastic PE, chemical PE, and gravitational PE. Explanations of the 3 were given.

A quick review of the work formula and the physics definition of work... The fact that work is done to lift a mass above the floor, but no work is done while the mass is being held up, is due to the fact that there is no movement on the mass. The 2 categories of work were listed and discussed. The first being work done against another force, like elasticity, gravity, and friction. The second is work is done when the speed of an object changes. A few problems were presented and solved. Power was next discussed, as a rate change, involving time. Power being work done/unit of time, that is joules/sec. Joules/sec are Watts.

I continued to work with Marcel on his practice test. We studied problems dealing with motion in one direction influenced by wind or water moving at a perpendicular angle to that motion. The problem is to calculate the resultant vector. We also worked on projectile motion for an object launched at an angle. There was no assignment.

I checked Marcel's work on the assigned homework problems and his work was very well done. I then gave him a copy of my practice test on two-dimensional motion. Problems included objects launched at horizontal and non-horizontal angles, objects moving through a cross-current, and algebraic vertor addition. There was no assignment.

Review of definition of force... Example of push on a wall, with the wall pushing back with the same magnitude but different direction... Discussion that a pair of forces are acting, an action force and a reaction force... Statement of Newton's third law and restatement into action and equal and opposite reaction... Examples of walking, driving and swimming used as action-reaction forces... If force=mass x acceleration, then acceleration is directly proportional to force and inversely proportional to mass.