Protons for Breakfast

Week 1: Electricity

November 2012

In the event of an alarm sounding…

Toilets…

Parents and children…

The plan for the evening…

7:00 p.m. to

7:59 p.m.

8:00 p.m.to

8:29 p.m.

Walkabout 8:59 p.m.to

9:00 p.m.

Feedback

Talk

8:30 p.m.to

8:59 p.m.

More talk

Who is helping? Andrew HansonAndy KnottAveril HortonBufa ZhangCat FitzpatrickChantal MustoeClaire GreenwellDavid ClayDeborah LeaEdward BrightmanEmma WoolliamsGianluca MemoliJacquie Elkin James ClaverleyJames MiallJane BurstonJane Scott

   

Paul GreenPeter BensonPeter EdmeadPeter Nisbet-JonesPeter QuestedPeter WoolliamsPippa GoldenbergRainer WinklerRalf MouthaanRobert GoddardRuth MontgomeryRuth PearceSharmila HansonStephanie BellSue Gibbons

Jeff FlowersJenny HullyJenny WilkinsonJohn GallopJohn MakepeaceJohn MountfordJonathan PearceJordan TompkinsJoseph ThomKate WilkinsonLaurie WinklessLindsay ChapmanLloyd EnglandLouise BrownMaria LodeiroMarta Doval MinarroPaul Carroll

Thanks

• NPL:

The National Physical Laboratory

• Serco:

Manage NPL on behalf of the BIS

• Amey:

Who set out the rooms

Michael de Podesta

Age 52:

• Lecturer in Physics at University of London for 13 years

• Understanding the Properties of Matter

• At NPL for 12 years.

• Most accurate thermometer ever made!

• International Surface Temperature Initiative

• Married with two sons(aged 14 & 16)

• Keen on Water Rockets

Member of the Most Excellent Order of the British Empire!

Why am I here?

I am here because I believe …

Science is humanity’s greatest achievement

Why are you here?

• Accompanying my daughter but also interested in how science is applied in everyday life.

• Science teacher has suggested it• Supporting my daughters who both love Science and keep

asking questions I can't answer!.• Fun• I have been home tutored since May and my science

teacher has been amazing and taught me so much. I am really interested in science and particularly the universe.

• My husband had a physics PhD and my youngest son has just graduated from Imperial with a physics degree and I would like to be able to join in their conversations sometimes.

• I like atoms

…there is a problem about how we, as citizens, relate to science…

The image of science:1Mad Muppets top cult science poll

Dr Honeydew is known the world over for his disastrous research at Muppet Labs,

"where the future is being made today".

His experiments invariably go awry, with poor old Beaker usually being blown to bits or electrocuted. BBC 6/9/2004

The image of science:2Science Gone Wrong

The final touch… What! BANG!

Alex Noble (Age 9)

The image of science:3An un-scientific experiment

Scientist

……… Scientist

In contrast…

• A room full of people who want to learn about science

• Helped by volunteers

• In a world where ignorance makes us powerless

Tonight’s talk

• The scale and size of the Universe

• Electricity

• How Electricity works

• Atoms

• Light

Tonight’s talk

The scale and size of the Universe

or

‘How not to be boggled!’

The imperceptible and the vast

As human beings we can judge:

temperatures close to ‘normal’

weights greater than a gram up to around 1000 kilograms

distances greater than a millimetre or less than a few kilometres.

times greater than a second or less than a fraction of a lifetime.

The imperceptible and the vast

As human beings we cannot judge:

temperatures more a few degrees away from ‘normal’Such temperatures just feel ‘very hot’ or ‘very cold’

weights beyond a few tonnes or less than a gramSuch weights seem either stupendously heavy or negligible

distances less than a millimetre or greater than a few kilometres.Such distances are too tiny or too far to perceive directly

times less than a second or more than a fraction of a lifetime.Such times are too small or too long for us to appreciate

The imperceptible and the vast

Measuring instruments extend our sensesTelescopes & Microscopes,

Weighing machines,

Devices sensitive to electricity & light,

Clocks

NPL: Enables people to trust measurements

Quantities and qualities that extend beyond our ability to

perceive them seem: imperceptible or vast

? ?Science helps us extend our senses

But we can still feel boggled!

Diameter:

12,800 km

Deepest hole: 10 km

Atmosphere: 10 km

The Planet Earth

Photo Credit: NASA

The Moon

Diameter

Earth:

12,800 km

Moon:

3476 km

Photo Credit: NASA

The Sun

Diameter: 1,390,800 km

Photo Credit: NASA

Powers of Ten

I hope that you are now a little unsettled and ready to go on a 9 minute journey to see how the world looks at different levels of ‘fantasy

magnification’

Photo Credit: Powers of 10

Very Very Small

Very Very

Large

Powers of Ten (1)

1 metre

1000 m

1000000 m

1000000000 m

1000000000000 m

0.001 m

0.000001 m

0.000000001 m

Can you see the problem with very small and very large numbers?

Powers of Ten (2)

Very Very Small

Very Very

Large

1

1000103

106

109

1012

1015

1000000

0.00110-3

10-60.000001 1018 1024 1030 1036

1021 1027 103310-15 10-9

10-18 10-12

100

Powers of Ten (3)

Very Very Small

Very Very

Large

1 metre

103

106

109

1012

101510-3

10-6 1018 1024 1030 1036

1021 1027 103310-15 10-9

10-18 10-12 1012

1000000000000 m

0.000000000001 m

Powers of Ten Length Scale in metres

Very Very

Large103

106

109

1012

101510-3

10-6 1018 1024 1030 1036

1021 1027 103310-15 10-9

10-18 10-12

?Very Very Small

100

Human Relationships

Atoms & molecules

Nucleiof atoms

Current estimate of the size of the

universe

Nearest StarLight YearTallest MountainNanotechnology

Distance to the Sun

Diameter of the Earth

Diameter of a hair

MicrobesViruses

Quarks

Powers of Ten Length Scale in metres

103

106

109

1012

101510-3

10-6 1018 1024 1030 1036

1021 1027 103310-15 10-9

10-18 10-12 100

Human Relationships

Distance to the Sun

Atoms & molecules

Nucleiof atoms

Current estimate of the size of the

universe

Nearest StarLight YearTallest MountainNanotechnology

Diameter of the Earth

Diameter of a hair

MicrobesViruses

Quarks

Powers of Ten Global Warming

Very Very

Large

100

103

106

109

1012

101510-3

10-6 1018 1024 1030 1036

1021 1027 103310-15 10-9

10-18 10-12

Very Very Small

Human Relationships

The phenomenon of global warming involves physical processes with

length scales spanning 20 powers of 10!

Distance to the Sun

Tallest Mountain

Diameter of the Earth

Atoms & molecules

Microbes

Powers of Ten Nuclear Power

Very Very

Large

100

103

106

109

1012

101510-3

10-6 1018 1024 1030 1036

1021 1027 103310-15 10-9

10-18 10-12

Very Very Small

Human Relationships

Tallest Mountain

The issues surrounding nuclear power involve

physical processes with length scales spanning 25

powers of 10!

Nucleiof atoms

Distance to the Sun

Diameter of the Earth

Atoms & molecules

Microbes

Powers of Ten (time)Time scale in seconds

Very Very short

Very Very Long

100

103

106

109

1012

101510-3

10-6 1018 1024

102110-15 10-9

10-18 10-12

Time for a molecule to jiggle once

Light wave wiggles once

Earthmoves once

around the Sun

Estimated time since the big bang

Age of the EarthEnd of last ice age

Lifetime of a Civilisation

A human lifetime

Fastest response of human

eyeSound

travels 1 metre

1 second

The Universe

Its very big, but full of very small things

? ?

Tonight’s talk

• The scale and size of the Universe

Its very big, but full of very small things

• Electricity

• How it works

• Atoms

• Light

Electricity

Electricity

Electromagnetic waves

Electricity

Heat

How it all fits together…

Atoms

Eeeee - lec- tric-ity Electricity

Electricity

Some experiments…

Lets take a look at some odd phenomena…

• A balloon and a piece of paper

Lets take a look at some odd phenomena…

• If I balance my glasses carefully…

Even a sausage…

• Sausages…

…its everything…

The balloon affects anything and everything nearby

To understand this, we need to understand • what matter is made of, and • how this ‘influence’ is communicated across ‘space’

• Scientists can develop instruments to measure the relative strengths of the ‘electric influence’

• Based on the same effect we saw with bits of paper

A simple scientific instrument: The gold leaf electroscope

The Van de Graaff Generator

Photo Credits: Katherine Robinson and MIT

• Scientists can develop machines to automate and amplify the ‘rubbing’ process with the balloon

The Van de Graaff Generator

It is not important to understand how a Van de Graaff generator works

PictureCredits: http://www.ikp.uni-koeln.de/~3T/tandem-prinzip1.htmlhttp://science.howstuffworks.com/vdg1.htm

The Van de Graaff Generator

It is not important to understand how a

Van de Graaff generator works

The Wimshurst Machine

Sorry: I cannot explain how a Wimshurst Machine works!

Photo Credits: Wikipedia and http://www.coe.ufrj.br/~acmq/electrostatic.html

Electrostatic Generators

• People have been doing this for a long time…

Photo Credits: http://www.ikp.uni-koeln.de/~3T/tandem-prinzip1.html

Conclusion…

Electricity is present inside ALL matter

Its ‘influence’ can be communicated

across ‘empty’ space

Tonight’s talk

• The scale and size of the Universe

Its very big, but full of very small things

• Electricity

It’s everywhere!

• How it works

• Atoms

• Light

Not Stuff • the gaps in

between matter• fields

Stuff • matter

How do we describe the world?

How do we describe the world?

How do we describe the world?

Not Stuff (Fields)• Fields

GravitationalElectroweakStrong

• Extend throughout space

Stuff (Particles)• Atoms

• Electrons• Neutrons• Protons

• Very small

We need to know about both particles and fields

Two different kinds of physical entity

How do charged particles interact?

It’s a three-step process…

Particle

with electric charge

Particle

with electric charge

Interact by meansof an electric field

…but the steps happen very quickly

How do we describe the world?

The electrical nature of matter

• Electric charge is a fundamental property of electrons and protons.

• Two types of charge (+ and -)If particles have the same sign of electric charge they repelIf particles have different signs of electric charge they attractThe forces (attractive or repulsive) get weaker as the particles get further

apart.

Tonight’s talk

• The scale and size of the Universe

Its very big, but full of very small things

• Electricity

It’s everywhere!

• How it works

There are ‘particles’ and ‘fields’

• Atoms

• Light

Electromagnetic waves

Electricity

Heat

How it all fits together…

Atoms

Atoms

Atoms

Protons, neutrons and electrons normally exist inside atoms

Atoms are small• Think of a millimetre

Atoms

1 mm

0.1 mm0.01 mm0.001 mm

• Atoms are roughly 10,000 times smaller than this…

Atoms

• There are VAST numbers of atoms in everything.

In just a handful of anything there are about the same number of atoms as there are grains of sand on all the beaches and deserts on Earth combined

Photo Credit: http://www.morguefile.com ID = 104101

The electrical nature of matter

AtomsInternal Structure

How are atoms made?

proton

Interact by the short range ‘strong’ force – not electrical

Electrical Repulsion

How are atoms made?

Atomic Structure

Electrons• ‘orbit’ around the outside of an atom• very light• possess a property called electric charge

Nucleus• occupies the centre• very tiny and very heavy• protons have a property called electric charge• neutrons have no electric charge

Atomic Structure

• Nuclei (+) attract electrons (-) until the atom as a whole is neutral• The electrons repel each other

They try to get as far away from each other as they can, aand as near to the nucleus as they can

The electrical nature of matter

ChemistryAtoms, Elements & Molecules

Atoms &… The Periodic Table

• Atoms with up to about 82 protons can be stable.• A material made up of a single type of atom is called an element

H

Atoms &… Molecules

H2

N

N

• A molecule is a collection of atoms stuck together electrically.

H

H

O

H2O

H

N2

Atoms &… Ions

• A ion is an atom or molecule which has lost or gained an electron.

O HH −

The electrical nature of matter

Solids

Atoms in solids

• Atoms can be imaged on a surface

Photo Credit: Patrick Josephs Franks: NPL

The electrical nature of matter

• In ‘normal’ matter, there are equal quantities of positive and negative charge so that there is no attraction or repulsion of objects.

Object 1

Object 2

The electrical nature of matter

Mechanical Properties

Atoms and mechanics

• Whenever two materials touch, the forces between them are the forces between the outer (valence) electrons

• All mechanical forces are actually electrical in nature

Object 1

Object 2

The electrical nature of matter

Conductors and Insulators

Atoms in solids

Solids are made up out of lots atoms very close together.

If the electrons can’t move easily from atom to atom:

The material is called an insulator

If the electrons can move easily from atom to atom:

The material is called a conductor

The electrical nature of matter

Magnetic Forces

Magnetism

Electric

&

Magnetic

• We call forces ‘magnetic’ when both particles are moving with respect to us.

• They are still electrical in origin.

• This was first explained by Albert Einstein in his Theory of Relativity

The electrical nature of matter

How the balloon affected the paper…

Odd phenomena…

• A balloon and a piece of paper

Odd phenomena…

• A balloon and a piece of paper

Tonight’s talk

• The scale and size of the Universe

Its very big, but full of very small things

• Electricity

It’s everywhere!

• How it works

There are ‘particles’ and ‘fields’

• Atoms

They’re everywhere! And they are all electrical!

• Light

The electrical nature of matter

How is the electrical force transmitted from one charged

particle to another?

How do charged particles interact?

It’s a three-step process…

Particle

with electric charge

Particle

with electric charge

Interact by meansof an electric field

…but the steps happen very quickly

The nature of interactions (1)

Analogy with water level and water waves

Tonight’s talk

• The scale and size of the Universe

Its very big, but full of very small things• Electricity

It’s everywhere!• How it works

There are ‘particles’ and ‘fields’• Atoms

They’re everywhere! And they are all electrical!• Light

An electro-magnetic wave

Electromagnetic waves

Electricity

Heat

How it all fits together…

Atoms

Summary

• Physics concepts span vast ranges of mass, length and time.

• The universe has two kinds of objects in it: Matter and Fields

• All matter (on Earth) is made of atoms which interact electrically.

• In matter as we normally experience it, there are equal amounts of the two types of electric charge and their effects cancel

• If we add or remove some particles with electric charge from matter then we can see the electrical effects.

Homework

• Activity: Remember when you have your breakfast that you are eating protons and neutrons coated with tasty electrons.

• Research: What is the ‘frequency’ of your favourite radio station? Don’t just get the number (98.9, 198 etc.) get the units as well! They should be in

HertzKilohertzMegahertz

One minute feedback

• On the back of your handouts!• Rip off the last sheet• Please write down what is in on your mind RIGHT NOW!

A question? OKA comment? OKA surprising thought in your mind? I’d love to hear it!

On-line Resources

• www.protonsforbreakfast.org

This PowerPoint ™ presentation.

Handouts as a pdf file

• blog.protonsforbreakfast.org

Links to other sites & resources

Me going on about things

See you next week!

Don’t forget your pencils and badges!

Goodnight

Goodnight