Recalling the definition of acceleration as change in velocity/time interval, we led into the idea that force causes acceleration. Unbalanced forces acting on an object cause the object to accelerate. Acceleration is directly proportional to the net force acting on it. Demonstrating the effects of increase mass on acceleration, we conclude that for a constant force, an increase in the mass will result in a decrease in acceleration. Acceleration is inversely proportional to mass. Newton's second law states that the acceleration produced by a net force on an object is directly proportional to the magnitude of the in the same direction, and inversely proportional to the mass of the object.

A test covering the physics of speed, velocity and acceleration was given. The use of the proper formula was required, and the method of solving needed, as well as the answer.

The answers to the homework problem were discussed. The formulas used to arrive at those answers were listed and placed into the list of formulas. The graph of speed v time for a given set of parameters was done, and the graph analyzed as to the type, relationship of the time to speed and slope. The constant slope was indicative of acceleration. A graph of distance v time for free fall was also propagated and analyzed. This graph was a parabola and showed the relationship that the distance quadrupled when the time doubled. The slope was shown to be the velocity and was constant at 10m/s/s. The difference of how fast,how far, and how quickly was discussed and the formulas again listed.

A review of free fall and the acceleration due to gravity started the class since Abby had missed a few lessons last week. Using the knowledge of the acceleration of gravity, the instantaneous speed of a falling object was determined at 5, and 6 seconds. From this, the average speed was calculated at 5, and 6 seconds. The distance an object will fall from rest, given the instantaneous speed was determined. The description of the motion of an object thrown upward, and then allowed to fall was elicited and the velocity at different times upward and downward calculated. A three-part problem was given for homework.

An example of an object tossed up from rest, allowed to reach its apex, and then travel down was used. Describing the motion in both directions would be part of the lesson. How to determine the velocity at given times in the upward travel and the downward travel, along with the distance covered would be determined by realizing that the velocity up would equal the velocity down for the same period of elapsed time. The formulas would be used to determine the velocity up after 1,2, and 3 seconds, and the velocity down after 4sec(which is 1 sec down from the apex), 5 seconds ( 2 sec down) and so on. The acceleration of gravity is known so the distance traveled can be calculated

3 problems determining the acceleration of an object were worked on, both as a review and a lead in for bodies in free fall. A series of questions involving an object dropped from a height led to the definition of free fall, as an object moving under the influence of gravity only. Air resistance was considered minimal and did not enter into the definition. A chart of instantaneous speed at intervals of 1 second was outlined and the definition of elapsed time elicited. From the chart the formula for acceleration was determined and the acceleration due to gravity found as 9.8 m/sec/sec. The relationship between instantaneous speed, time, and acceleration was shown by the formula.

Lab measuring the average velocity of a dynamics cart at constant velocity and varying distances from zero. The time measured for each distance passage is used to determine the average velocity at 20 cm, 40cm and 60cm from zero. The average velocity is then used to determine the instantaneous velocity at each marker. Both the average and instantaneous velocities are plotted on a graph of time v velocity and the best line drawn. Homework questions were then reviewed post lab.

A lab to determine the average speed and the instantaneous speed of a cart and pulley will be determined with the distance set up. This lab will be completed on Tuesday, with some additions to the procedure.

A test on chapter 3 material was administered, this dealt with forces and friction. At the completion of the test, the answers were analyzed and the test graded. Speed and velocity were reviewed and this led into an investigation of acceleration, how it relates to velocity, and the formula for determining acceleration.

Question how we determine motion in an object. Demo with a small model car moving across the table and elicit that motion is relative to a stationary object. State that all motion is relative to a "stationary" object, even the Earth. State that when an object is moving it's position relative to a fixed point is changing. Unless otherwise stated, speed is relative to the Earth's surface. explain that the formula for determining speed involves distance and time. Discuss the difference between instantaneous speed and average speed, using examples. Elicit the difference between speed and velocity. Define velocity in terms of magnitude and direction.