Week 5

Energy, Energy Efficiency and Static Electricity

This week:

Complete focus questions in the logbook (include definitions, images and worksheets)

Carry out energy experiments - lemon batteries!

Identify different ways to measure energy

Understand energy efficiency

5. Watch a demo on static electricity (Van de Graaff generator) &

complete experiments on static electricity

Complete worksheets below

Work on logbook - this week's Focus Questions!

THIS WEEK'S FOCUS QUESTIONS!

(Answer these in your logbooks)

1.How do we measure energy?

a. Explain the different ways of measuring energy.

Give examples (energy, chemical energy, electrical energy etc)

2. What is meant by energy efficiency?

a.Give a definition and examples of energy efficiency

b. Explain how you could make your house more energy efficient..

3. What is Static Electricity?

a. Explain what static electricity is

b. include photos of the experiments

and worksheets completed in your logbooks

So, how do we measure energy?🤔

There are many different ways depending on the type of energy we are talking about.

In physics, the standard unit of measure for energy is the joule which is abbreviated as J. There are other units of measure for energy that are used throughout the world including kilowatt-hours, calories, newton-meters and electron volts.

PHYS 8.04 Units of Energy.pdf

What is energy efficiency?🤔

Let's revisit this video from Week 4..

Energy efficiency

The efficiency of a machine is a measure of how good the machine is at converting the input energy

to useful energy.

The percentage of input energy that is

converted to useful energy

is used to give a machine an efficiency rating.

We do the calculation like this:

USEFUL X 100 TOTAL

You can find more in Chapter 3 of your text.

Let's have a go at calculating energy efficiency

with this worksheet..

8.06 Energy Efficiency Worksheet.pdf

PHYS 8.06 Energy Efficiency

What is Static Electricity?

tenor.com/RgtW.gif

THERE ARE TWO TYPES OF ELECTRICITY THAT YOU NEED TO KNOW ABOUT

1. CURRENT (electricity that moves in circuits)

and

2. STATIC (electricity that jumps across surfaces)

Watch this video👇🏼and take notes in your workbook - it explains the difference in these two types of electricity really well 🙌🏼

Static means the electricity is 'not moving'

around a circuit.

static... stationary electricity

Because of friction the charged particles (electrons) are sitting....

and waiting for contact with a surface that will cause a.... ZAP⚡️

This ZAP⚡️ is electrons jumping from

one surface to another.

This is static electricity!

👉🏼 Conductors like metals tend to have loosely bound outer electrons, which can easily flow between surfaces/materials.

Insulators, like plastics, rubber and glass have tightly bound electrons that won't readily flow between surfaces/materials.

Static is most likely to occur when one material is an insulator like carpet. Electrons from your body will move to the carpet as you walk. This will make your body more 'positively charged' so when you then touch a conductor that is ripe with negatively charged electrons (a metal door knob for example) you will experience a ZAP⚡️

In summary, if you place two different materials next to each other, electrons will start jumping from one material to the other.

Friction gives loosely-bound electrons the energy to leave their atoms and migrate to other surfaces.

Friction can cause Flying electrons

Read through this powerpoint below to learn more🤩