In 1771, Luigi Galvani discovered that the muscles of dead frogs twitched when struck by a spark

May have inspired the idea behind the story Frankenstein

Generation of Electricity = [Coil of Wire] +  [Magnetism] +  [Relative Motion]

The basic components are:1. Power Plant: Electricity is

produced here2. Power Grid: A network that

connects power plants to substations and substation to homes.

3. Transmission Substation: Transformers increase voltage so that volts can be sent over long distances.

4. Distribution Substation: Transformers reduce voltage to a level suitable for the surrounding community

5. Distribution System: Delivers electricity to homes and businesses. Line may be a underground or overhead.

6. Service Connection: Connection of customers to the grid. A meter is connected also to measure the amount of electricity used by customers

When you switch something on, you complete a pathway for electricity to flow through.

The pathway that allows electrical energy to flow is called an electric circuit.

Electric circuits consist of three components: A Power Supply: Provides electrical energy A Load: Converts electrical energy into another

form A Conducting Path: Allows electric charge to

flow around the circuit.

Electric circuits consist of three components: A Power Supply: Provides electrical energy A Load: Converts electrical energy into another

form A Conducting Path: Allows electric charge to

flow around the circuit.

Load

Power Supply

Conducting Path

=

=

=

Current measures the amount of charge flowing through a circuit .

A large current has more charge flowing every second than a small current.

Current is measured in a unit called ampere (A) or ‘amps’

Milliamps (mA) are used to measure small currents.

Current can be measured using a device called an ammeter.

Ammeter’s need to be inserted into the circuit to get a reading.

Voltage is measure in Volts (V)

A device that measures the amount of volts passing through a circuit is called a voltmeter

Voltage is a measure of the amount of energy there is to push charge through a circuit.

Voltage is supplied by batteries, power packs and power points.

Batteries, power packs or power points are all considered energy sources.

They provide all the electric energy and voltage to a circuit.

Energy sources create an electric field that pushes electrons around a circuit.

Power points supply approximately 240 volts into your home

Power packs like the ones we use in class supply up to 12 volts

The power for which is produced in a variety of power plants.

Batteries are used when we need portable energy sources.

1 AA battery provides 1.5 volts

While car batteries provide 12 volts

Batteries are made up of cells.

These cells can be either wet or dry.

In this wet cell, zinc reacts with the acid and releases electrons.

If a circuit is connected to the plates then the electrons will flow to the copper plate

As they flow through the circuit the globe will light.

Wet cells are usually large and heavy and can leak acid if tipped over.

A car battery is a collection of wet cells.

The wet substance is sulfuric acid

The plates are made of lead and lead oxide.

While a car is running it reverses the chemical reaction recharging the battery.

Eventually chemicals build up on the plate and the batter “dies”.

Being large and heavy wet cells are useless for small devices like:

▪ Ipods▪ Laptops▪ Remotes

They use small portable cells called dry cells.

Dry cells contain a chemical paste and their electrodes are designed to save space.

It is common that several batteries are connected together to supply more voltage.= 4.5 volts

A photovoltaic cell (or solar )is made up of two layers.

These two layers are semiconductors.

When sunlight strikes the top layer electrons are given energy to move to the bottom layer.

This creates an electric current.

Aka the electric eel Actually a

freshwater fish. It can produce up to

600 volts This is five times

the amount found in an electrical outlet

Uses the electric field to stun fish and to see

electrolocation

http://wsc.pv.unsw.edu.au/

This website allows you to build and name a virtual solar powered car

You are then able to race it against computer generated cars.

The important feature of this game is the design process.

You have a limited budget of $240,000 to build your car.

You need to decide on what balance of components are important for speed and power.

A conductor is a substance that allows current to flow through it easily.

Examples are metals like:▪ Copper: used commonly in electric circuits ▪ Aluminium: More expensive, used when copper is

unsuitable.

Materials that do not allow current to pass through them are called Insulators.

Examples of insulators: ▪ Plastic ▪ Rubber

Brief research assignment.

What are superconductors ?

What uses are there for superconductors?

Briefly describe how they work.

Useful links: http://

superconductors.org/INdex.htm

http://science.howstuffworks.com/question610.htm

All metals conduct electricity, but some do so better than others.

Tungsten and nichrome for example are not very good at conducting electricity.

Therefore electricity flows easier in copper wires than in tungsten.

This is called resistance.

Resistance converts electrical energy into heat and light.

This is used in light globes with tungsten filaments.

Conductors have a low resistance

Insulators have a high resistance

Without any resistance (such as a globe or heating element) too much current can flow through a circuit.

This may generate too much heat in connecting wires or the energy source.

This might damage the circuit causing it to melt or catch fire!

This is known as a Short Circuit

If two globes are arranged in a single line then they are said to be in series.

Although the current is said to each globe is the same, the voltage is shared between the two.

This means that the globes will both glow more dimly.

If one of the bulbs is removed or ‘blows’ then the other globes in the circuit will not light up.

If two globes are arranged in separate branches of a circuit then the are said to be in parallel.

Each globe has the same amount of energy and voltage supplied to them .

The current is divided between them, This means that they will glow with the same ‘brightness’ Also if one globe is removed from this circuit the other will

still remain lit.

SERIES PARALLEL

A series circuit arranged of 20 lights would share 240 volts from a power point.Therefore each globe receives 12 volts.

Disadvantages: • If one globes broke then all the other globes with also go out• This would make it difficult to find the bad globe.

In a parallel circuit all lights are powered by a low voltage source. A transformer reduces the voltage from 240 volts to 12 volts. All globes receive 12 volts.

Advantages: • If one globes breaks all the other globes still have power. • This makes it easier to find the broken globe.

Type of Circuit

Voltage Current

Series Split Normal

Parallel Normal Split

Circuits can be combinations of series and parallel sections.

Current will always take the easiest way through a circuit. A section with a single globe will be easier to travel on

than a section with two. Also it will carry twice as much current.

Electrical wiring within you house is one big parallel circuit

Electrical companies supply 240 volts to your house.

Each power point creates an extra parallel section that receives the same 240 volts.

Direct Current (DC) When the current flows

in only one direction. An example of this is a

battery. Alternating

Current (AC) Current flows

backwards and forwards.

Energy is supplied to houses like this because it is easier to generate and transmit.

What is wrong with this picture?

Short circuits occur when an easier path for current is created.

A huge current flows through causing the circuit to overheat and melt.

You could even become part of the circuit and be shocked or electrocuted!

To prevent this home circuits have fuses or circuit breakers.

What's wrong here?

A fuse is a thin metal wire, that breaks when too much current passes through it.

Fuses are rated according to the amount of current that causes them to melt.

Therefore a 5 amp fuse will melt at a current of 5 or more amps.

Fuses used to be the most common method for protecting circuits within a house.

These days new houses are built with circuit breakers instead.

Circuit breakers are special switches that ‘trip’ (turn off) the circuit if too much current flows through.

Electric shock and electrocution (death by electricity) will occur if current finds a path through the body.

Only a small current can cause death.

The current damages your tissues and interferes with the electric signals that drive the heart and the brain.

Step 1: Climb electrical pole.

Step 2: Reach out and touch high voltage conductor.

Step 3: 16,000 volt Human fireball!

If you find someone who has collapsed from an electric shock: Call OOO Switch off main power (if

possible) Do not touch the person

(otherwise you will get shocked)

You may be able to move the person if you use an insulating material (plastic rope, garden hose)

The electric chair was invented to replace hanging as a method of execution.

It was intended to be a quick and painless alternative

In the first ever electric chair execution 1000 volts were applied.

This burnt skin and burst blood vessels

It still took another 70 seconds at 1300 volts to kill the prisoner.

Other prisoners convulsed so violently they broke their own arms and legs.

So really its not all that quick and painless !

Tour Guide Robot - Toyota Geminoid HI-1 -Hiroshi Ishiguro Asimo - Honda

ASIMO stands for Advanced Step in Innovative Mobility

ASIMO is a humanoid robot created by Honda motor company.

Height: 130 cm Weight: 54 Kg

By the end of 2007 there were only 46 ASIMO robots in existence.

Further Information: http://world.honda.com/ASIMO/

ASIMO evolution

• ASIMO has been in the making for 20 years

• In the picture above you can see the current ASIMO compared to its previous versions

Geminoid HI-1is a robotic replica of Professor Hiroshi Ishiguro.

Professor Ishiguro can operate Geminoid from a distance.

This allows him to give two lectures simultaneously at universities that are Km’s apart.

Further Resources: http://www.irc.atr.jp/

Geminoid/overview.html

Research a REAL robot

Create a presentation for the entire class

The selection of the robot is up to you

The form of the presentation is also up to you

Or make a Timeline of Robot development

Individually you are to design a robot to fulfil a specific function.

You must include a design of your robot with labelling to explain why each section is essential to its function.

You must also create a short comic strip that demonstrates your robot in action.