A 9th grade class can learn conceptual physics as students explore digital fabrication tools to design a pinball machine. When they laser cut their prototypes, students will gain an understanding of the applications of potential, kinetic and mechanical energy through simple and complex machines.
Lesson Overview (for students):
All mechanical energy is classified as either kinetic or potential. As students explore digital fabrication tools to design a pinball machine, they will gain an understanding of the applications of potential, kinetic and mechanical energy through simple and complex machines. By end of lesson, students will be able to design and build a digital fabrication pinball machine that will use at least one form of energy.
Conceptual Physics (9th Grade)
Conceptual Physics presents concepts of the major themes of physics. There are two ways that beginning students of physics can understand the topic: (a) through mathematical models, and (b) through concepts. This course takes the latter approach. The concept of energy is often introduced in the very first unit of 9th grade Conceptual Physics. Energy is a critical concept across all science disciplines and as such serves as both a disciplinary core idea in multiple disciplines and a crosscutting concept. It is essential for explaining a wide range of phenomena, solving problems that occur in everyday life, and learning other science ideas. For these reasons, energy plays a central role in the high school science curriculum.
Instructional Design: Confirmation Inquiry Level 3
Key Vocabulary Words:
Work, Joule, Power, Energy, Lever, Pulley, Force, Motion, Mechanical Energy, Potential Energy, Elastic Potential Energy, Chemical Energy, Gravitational Potential Energy, Kinetic Energy, Work-Energy Theorem, Law of Conservation of Energy, Machines, Efficiency, Watt, Horsepower
Forces and Motion
WORK = FORCE (X) DISTANCE
(W) WORK is the amount of FORCE needed to move an object a certain distance. Calculate the force in Newtons. (N) Work is done only when FORCE causes a change in the motion of an object.
JOULE = A Unit of WORK
(J) 1 N (x) m = 1 J (N = Newton)
1 Kg (x) m2/s2 = 1 J (Kg = Kilograms)
You will use the formula for Newtons (N) (X) distance in meters (m) equals JOULES (J). You will convert your mass to a FORCE in Newtons (N), then move the mass a certain distance in meters. The answer to the problem will be in JOULES of energy
ENERGY = The ability to do WORK
(E) Energy is measured in Joules
Law of Conservation of Energy = Energy cannot be created nor destroyed. Energy is our potential to do some type of work. We use energy constantly.
GRAVITY = Force of attraction between the two bodies of matter due to their mass. The Earth exerts a force on you of 9.8 m/s2. This is a constant and always applies, except in space.
Digital Fabrication tools used:
Step One: Teaching Phase: How will the teacher present the concept or skills to students?
Step Two: Making the base (Time 30-60 minutes)
Teacher Led Discussion: Gravitational potential energy depends on the height of an object above the ground. In the pinball machine a larger angle results in a larger gravitational potential energy therefore larger kinetic energy. Because KE = ½ mv2 higher kinetic energy translates to higher speed.
Step Three: Making the flippers (Approximately 30 minutes required)
Teacher Led Discussion: A bell crank mechanism transfers horizontal motion to vertical motion. Show student videos of bell crank mechanisms in motion.
Basic Bell Crank
Step Four: Make Push Buttons (Approximately 15 minutes required)
Step Five: Attaching the button to the flipper (5 minutes required)
Step Six: Making a launcher (5 Minutes required)
Teacher Led Discussion: The most common launcher for a pinball machine is a spring system, as seen in the picture to the right1. A spring system is very similar to a rubber band system because they both convert elastic potential energy to kinetic energy. A spring system can be stretched or compressed to gain elastic potential energy; however, a rubber band system can only be stretched. In the following directions, students will create a rubber band launcher. In the rubber band launcher pulling the paddle does work on the launcher mechanism creating elastic potential energy. When the system is triggered, the elastic potential energy is converted to kinetic energy putting the ball into motion. Students can develop alternate ball launching mechanisms such as a gravity ramp launcher or spinner launcher.
Picture from www.Pinballdecals.com
Step Seven: Making a ball catcher (5 Minutes required)
Placing obstacles on the playing field/decorating the pinball machine
Step Eight: FINAL PRESENTATION
Teacher Led Discussion: Teacher will discuss levers and inclined planes, which are two of the simple machines. In most cases simple machines are used to make our lives easier by requiring a smaller input force to get a larger output force. In the case of the flipper, we sacrifice the force advantage to gain a larger range of motion.
The inclined plane is the playing field of the pinball machine. By having an angle we increase the speed of the marble as it goes down the incline toward the flipper. This makes the game more exciting and challenging.