# Energy

Mechanical

## Content Overview

**Activities**

An Inclination - Compare the Work it takes to bring a cart to a height along a ramp at various angles

Pop Drop 'n Lock - Take measure and determine energy values from a dropper popper

Power of Fizz - Find out how many LED bulbs we can power from the eruption of Diet Coke and Mentos. Spoiler alert: it's less than one!

Energy Skate Park - PhET Simulation

**Topics**

Work

Potential Energy

Kinetic Energy

Conservation of Energy

Power

## Students are Expected to Understand

How Work Transfers Energy

Measuring and Determining Mechanical Energy, Work, and Power

Principals Behind Energy Transformations and Conservation of Energy

### Some Notes on Motion

- Work can be negative - (energy out) or positive + (energy in) to show the direction of energy
**transfer**but not the direction of energy itself as energy is a scalar quantity - Work can also be used to show energy transformation from one type to another, i.e. Potential turning into Kinetic Energy
- This unit focuses on
**Mechanical**Energy which is a type of energy that combines both Potential and Kinetic Energy - Potential Energy (PE) will assume that we're on Earth with a gravitational acceleration of g = -10 m/s² unless given otherwise
- Kinetic Energy (KE) is the energy of motion. Pay careful attention to the velocity in the equation KE = ½mv² as it has some interesting consequences
- It takes an exponentially greater amount (a much, much bigger amount) of KE to increase the velocity of an object

- Energy can be moved from one object into another but one can't really make it disappear - it just has to be placed elsewhere
- Generally, there's a finite energy to everything, including our own universe
- People frequently transform Kinetic Energy to Thermal Energy to stop moving via friction brake but now we're seeing more Kinetic Energy being transformed as stored electrical energy
- Perpetual motion machines can never exist due to 2nd Law of Thermodynamics as energy is continually lost to the environment around the machine

Energy is one of the large encompassing themes of this course. It allows us to further understand the sources of motion and opens up an important chapter on the impacts of energy in our lives

Crash Course - Work, Energy, and Power Khan Academy - Work and energy the Physics Classroom - Work, Energy, and Power

**These videos are to be used as a supplement and are not a replacement for in-class experiences*