Monday, January 4th, 2016 Starting our New Unit! Energy and Heat

On This Day in History! January 4 th, 1643 the world loses the great Galileo, and gains Sir Isaac Newton!

This Day…TODAY! Scientists have formally adopted four NEW elements to add to our Periodic Table of Elements.

Today’s Targets I can define and explain how energy is conserved (#1) I can mathematically and conceptually describe the two primary “States” of energy. (#2) I can identify the transfer of energy among the 6 “Forms” of energy. (#3) I can define the term energy (#4)

Today’s Agenda Introduction (Energy) Brave students??? Diagram time (The Pendulum) –States of Energy –Conservation of Energy Picture time (marrooned) –6 Forms of Energy Exit Evaluation

What is Energy? Classical Definition: More applicable at this time: Energy – the ability to do work. Energy – the ability to cause change. The SI (Le Systemme Internacional de Unites) for Energy = Joules (J)

I need 2 BRAVE student volunteers. The Pendulum –Perhaps the most important machine of all TIME! –The simple pendulum was/is used to: Uncover the laws of gravity Discover the laws of planetary motion Illustrate the conservation of energy Demonstrate wave (harmonic) motion And MORE!!!

Why CAN’T the pendulum hit the student? Because Energy is CONSERVED. The TOTAL energy of the system is maximized at the first moment (release point) When the “bob” is released, energy is converted from stored (potential) to active (kinetic). Upon return, the “bob” can have no MORE energy than it’s initial position.

Let’s Draw it Out!!! See smartchart

So Why Doesn’t the Pendulum Just Keep Going Forever??? If energy is truly “conserved”, then the pendulum should continue to swing indefinitely! Where does the energy go? Are Potential and Kinetic Energy sufficient to describe all energy in the universe??? –Yes and...No

A Different Perspective Sometimes it’s more appropriate to view energy through a different lens than the two “states” –Potential (stored) and Kinetic (motion) Let’s assume the perspective of viewing energy via the 6 “forms” of energy. See smartchart

So the 6 forms are… Nuclear – energy contained within the nucleus of atoms (fusion and fission) Radiant – energy that travels as electromagnetic waves. Thermal – the total kinetic energy of all the particles that makeup an object. Chemical – energy locked in the bonds between atoms. Mechanical – energy of moving matter. Electrical – energy of moving electrons. Sound – energy of traveling compression waves.

Practice Problem Pendulum (applying the Conservation of Energy Mathematically) Remember: – PE = Stored Energy – KE = Energy of Motion See smartchart

Exit Evaluation 1.Stored energy is also called ______ energy. 2.Energy of motion is also called ______ energy (state). 3.Energy is neither created nor destroyed, it is _________. 4.List the six “Forms” of energy: Potential Kinetic Conserved Nuclear Radiant Thermal Chemical Mechanical Electrical Sound