Using sketches of a box sitting on the table, the forces if gravity, tension, and forces pulling toward the right and left are shown as vectors. The length of the vectors indicate the relative size of the forces. Vector quantities are defined as having magnitude and direction, examples are weight and velocity. Mass, time, liquid measurement, and area are defined as scalar quantities, containing magnitude but no direction. A kilogram mass was hung from a spring balance and the force shown as about 10 Newtons. The forces were labeled positive and negative and the net force shown as zero. The equilibrium rule was derived as "the sum of the forces equal zero in a state of no physical change. Two spring balances suspended a small shelf of wood and 2x250 gram masses were placed, one at each end. The sum of the downward forces equaled the sum of the upward forces. As one mass was moved closer to the other, the force increased on one side and decreased on the other, however, the net sum was always the same. A thought problem regarding how much would each of two scales show if you stood with one foot on each.

The class was started with a few review questions regarding hypothesis and law. Some demonstrations of thermal and mechanical equilibrium were used and a definition derived for equilibrium. Using spring balances and a large wooden block and masses, it was shown that a force is applied to change the equilibrium. The states of motion, rest and movement, were both shown to need a force to change their state of motion. The definition of a force was elicited. Examples were drawn on the board to show the derivation of a net force, and that the unit of force measurement is the Newton (N). The stretching of the spring in the balance was noted and named the "stretching force" which is referred to as tension. The formula for determining the weight as weight=force of gravity x mass was given and the force of gravity (g) shown as 9.8 Newtons.

The class was started by solving a few physics mathematical problems which reinforced the solving for unknowns and the importance of the use of units. A discussion of the differences between a fact, a hypothesis, a law or principle, and a theory was outlined with some examples and demonstrations of each. Reflection from a plane mirror was demonstrated with a laser and mirror, the rays identified and the angles formed by the incident ray and the reflected ray were shown to be equal, always. This was an example of a law. A series of statements was outlined, and Abby was asked to determine if they were a hypothesis?

Reviewed and added to the discussion regarding falling bodies and their mass. We extended the concept to demonstrate that there are factors which will affect the rate of fall. A demonstration of an index card left whole and one which was folded in fourth's, both dropped together, with the folded card reaching the ground first. This demonstrated that even though the mass was equal, the shape had an effect on how the air molecules held up the unfolded card. The basic SI units were listed for length, mass, time, temperature and amount of substance, along with their symbols. The derived units were shown like joules and coulombs to be combinations of the basic units. The commonly used prefixes were listed. Some problems were worked using basic formulas and derived units.

Course requirements were discussed. The branches of science into living (life) science and nonliving (physical) science were outlined. A launch lab was performed by Abby which involved determining the rate of fall of 4 nickels taped together compared to one nickel. The hypothesis was elicited that the 4 nickles should fall 4 times as fast, being 4 times heavier. The experiment was done to prove or disprove the hypothesis. A discussion as to what factors might effect the rate of fall followed. Mathematics, being the language of physics was presented to stress that ideas are unambiguous when expressed in mathematical terms. 2 + 2 equals four, not sometimes, but always. A simple problem to determine the resistance in an electric circuit was presented, along with the formula, variables and units. This was done to stress that their are no double meanings in the language of physics. The areas of the physical world to be studied in physics was presented. An assignment to briefly research the concept of natural philosophy as presented by Aristotle was given.

He took his final for this semester. He scored a 80/100.

He never showed up online. I waited for him.

Initially, he did his homework from Monday. Then, we reviewed for the final.
He has an activity sheet for homework due on Monday on kinematic equations.

He received an 83% on his circuits test that we went over. Then, we started to review for his final.

Vlad is taking his circuits test today.