1. Notes & Calculations

2.  You will build a kicking machine that will kick a Ping-Pong ball into a cup lying on its side 12 inches away.  You must use:  A pendulum  A rubber band  A Combo of the two

3.  You will be able to calculate:  The velocity of your ping pong ball  The acceleration of your ping pong ball  The force your kicking machine exerts on the ball  The Kinetic Energy the ball possesses as it is shot forward  You will also understand how kinetic energy and potential energy are related

4.  In the following slides we will discuss how to calculate velocity, acceleration, force, and KE.  You will be given a calculations worksheet at the end of these notes to check your understanding before we move into the lab so I suggest you take notes on these equations.  At the end of this lab you will be given a test over the vocab & calculations we covered in this unit so be prepared!

5.  Velocity: the speed and direction of a moving object  To calculate velocity: V = Δ d ÷ Δt V = (d f – d i ) ÷ (t f –t i ) V Δd Δt ÷÷ ×

6.  Acceleration: the rate of change of velocity (a change in velocity over a period of time)  To calculate acceleration: a = Δv ÷ Δt a = (v f – v i ) ÷ (t f – t i ) a Δv Δt ÷÷ ×

7.  Force: a push or pull exerted on an object  Newton’s 2 nd Law: states that the acceleration of an object is in the same direction as the net force on an object, and that the acceleration of an object is the net force divided by its mass  Basically: F = ma  To calculate force:  Force = mass X acceleration ▪ F = ma

8.  Kinetic Energy: energy an object has due to it’s motion  To calculate KE: KE = ½ mass x velocity 2 KE = ½mv 2

9.  Potential Energy: energy that is stored due to the interactions between two objects  To calculate potential energy: PE = mass x gravity x height PE = mgh  Potential energy and Kinetic energy are inversely related  This means that when one increases the other decreases

10.  Law of Conservation of Energy: energy cannot be created or destroyed only transformed into a different form  This means that the ping pong ball sitting in your device will have stored (potential) energy. When your device “kicks” it, it begins to move and thus energy has transformed from potential to kinetic.

11.  The calculations worksheet is homework and will be due Wednesday at the beginning of class.  If you have questions come see me before then b/c we will not spend class time working on them after today.  If you lose the worksheet do not ask me for another copy. Everything is on my website and you are responsible for printing you another copy if you loose the one I provide you.

12.  Remember:  Calculations due Wednesday  Tomorrow you will get with a partner to design your kicking machine and figure out when/how you will take measurements for your calculations  Sometime mid-unit (while we are working on this lab) there will be a quiz over the material we are covering  At the end, after you have completed the lab, there will be a test over this material!