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cell energy electron lamp

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Page 1: ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ cell energy electron lamp. Coulomb of charge (electrons) Think of it as a “bag of electrons” (containing 6250000000000000000 electrons!)

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cell

energy

electron

lamp

Page 2: ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ cell energy electron lamp. Coulomb of charge (electrons) Think of it as a “bag of electrons” (containing 6250000000000000000 electrons!)

Coulomb of charge (electrons)

Think of it as a “bag of electrons” (containing 6250000000000000000 electrons!)

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Page 3: ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ cell energy electron lamp. Coulomb of charge (electrons) Think of it as a “bag of electrons” (containing 6250000000000000000 electrons!)

Current

The number of Coulombs flowing past a point in the circuit every second.

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A

I’m counting how many

coulombs of electrons go

past me every second

1 Amp = 1 coulomb per second

Page 4: ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ cell energy electron lamp. Coulomb of charge (electrons) Think of it as a “bag of electrons” (containing 6250000000000000000 electrons!)

Voltage(emf)☺

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☺V

I’m checking the difference in energy (per

coulomb) between the 2 red arrows

1 Volt = 1 Joule per coulomb

Page 5: ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ cell energy electron lamp. Coulomb of charge (electrons) Think of it as a “bag of electrons” (containing 6250000000000000000 electrons!)

Voltage (p.d.)☺

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V

I’m checking the difference in energy (per

coulomb) before and after the lamp

1 Volt = 1 Joule per coulomb

Page 6: ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ cell energy electron lamp. Coulomb of charge (electrons) Think of it as a “bag of electrons” (containing 6250000000000000000 electrons!)

Draw the sentence

1. Electricity is the flow of electrons.

2. We measure the quantity of electrons in Coulombs.

3. One Amp means one Coulomb of electrons flows round every second.

4. The electrons carry energy from the cell to the lamp.

5. The electrons then return to the cell to get more energy.

6. The electrons are NOT used by the lamp.

7. Voltage measures the amount of energy each coulomb receives or gives.

8. Physics is the most important subject Science subject!

Page 7: ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ cell energy electron lamp. Coulomb of charge (electrons) Think of it as a “bag of electrons” (containing 6250000000000000000 electrons!)

Cell and battery of cells

Page 8: ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ cell energy electron lamp. Coulomb of charge (electrons) Think of it as a “bag of electrons” (containing 6250000000000000000 electrons!)

d.c. power supply

Page 9: ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ cell energy electron lamp. Coulomb of charge (electrons) Think of it as a “bag of electrons” (containing 6250000000000000000 electrons!)

a.c. power supply

Page 10: ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ cell energy electron lamp. Coulomb of charge (electrons) Think of it as a “bag of electrons” (containing 6250000000000000000 electrons!)

Lamp

Page 11: ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ cell energy electron lamp. Coulomb of charge (electrons) Think of it as a “bag of electrons” (containing 6250000000000000000 electrons!)

Resistance of a filament lamp

• Resistance increases as the current increases (because the wire gets hot)

Current

Voltage

Page 12: ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ cell energy electron lamp. Coulomb of charge (electrons) Think of it as a “bag of electrons” (containing 6250000000000000000 electrons!)

open switch

Page 13: ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ cell energy electron lamp. Coulomb of charge (electrons) Think of it as a “bag of electrons” (containing 6250000000000000000 electrons!)

Ammeter

Page 14: ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ cell energy electron lamp. Coulomb of charge (electrons) Think of it as a “bag of electrons” (containing 6250000000000000000 electrons!)

Voltmeter

Page 15: ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ cell energy electron lamp. Coulomb of charge (electrons) Think of it as a “bag of electrons” (containing 6250000000000000000 electrons!)

Resistor

Page 16: ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ cell energy electron lamp. Coulomb of charge (electrons) Think of it as a “bag of electrons” (containing 6250000000000000000 electrons!)

Variable resistor (rheostat)

Page 17: ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ cell energy electron lamp. Coulomb of charge (electrons) Think of it as a “bag of electrons” (containing 6250000000000000000 electrons!)

Bell/buzzer

Page 18: ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ cell energy electron lamp. Coulomb of charge (electrons) Think of it as a “bag of electrons” (containing 6250000000000000000 electrons!)

Thermistor

• Resistance decreases with increasing temperature

Temp

Resistance

Page 19: ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ cell energy electron lamp. Coulomb of charge (electrons) Think of it as a “bag of electrons” (containing 6250000000000000000 electrons!)

Light-dependent resistor (LDR)

• High resistance in the dark but a low resistance in light

Page 20: ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ cell energy electron lamp. Coulomb of charge (electrons) Think of it as a “bag of electrons” (containing 6250000000000000000 electrons!)

Diode

• Allows current to flow in one direction only (from + to – in the direction of the “arrow)

Page 21: ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ cell energy electron lamp. Coulomb of charge (electrons) Think of it as a “bag of electrons” (containing 6250000000000000000 electrons!)

Current

The number of Coulombs flowing past a point in the circuit every second.

☺☺

☺☺☺

A

I’m counting how many

coulombs of electrons go

past me every second

1 Amp = 1 coulomb per second

Can you COPY

the blue writing

please?

Page 22: ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ cell energy electron lamp. Coulomb of charge (electrons) Think of it as a “bag of electrons” (containing 6250000000000000000 electrons!)

Current

I = Q/t

Where I = current in Amps

Q = charge (# of electrons) in Coulombs

t = time in seconds

Page 23: ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ cell energy electron lamp. Coulomb of charge (electrons) Think of it as a “bag of electrons” (containing 6250000000000000000 electrons!)

In a series circuit

Current is the same at any point in the circuit

2.5 A

2.5 A 2.5 A

2.5 A

Page 24: ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ cell energy electron lamp. Coulomb of charge (electrons) Think of it as a “bag of electrons” (containing 6250000000000000000 electrons!)

In a parallel circuit

The current splits (total current stays the same)

2.5 A

2.5 A

1.25 A

1.25 A

Page 25: ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ cell energy electron lamp. Coulomb of charge (electrons) Think of it as a “bag of electrons” (containing 6250000000000000000 electrons!)

Milliamps!

1 A = 1000 mA

1 mA = 0.001 A

Page 26: ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ cell energy electron lamp. Coulomb of charge (electrons) Think of it as a “bag of electrons” (containing 6250000000000000000 electrons!)

Current

The number of Coulombs flowing past a point in the circuit every second.

I = Q/t

☺☺

☺☺☺

A

I’m counting how many

coulombs of electrons go

past me every second

1 Amp = 1 coulomb per secondCan you copy this please?

Page 27: ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ cell energy electron lamp. Coulomb of charge (electrons) Think of it as a “bag of electrons” (containing 6250000000000000000 electrons!)

Voltage(emf)☺

☺☺

☺☺☺

☺V

I’m checking the difference in energy (per

coulomb) between the 2 red arrows

1 Volt = 1 Joule per coulomb

Page 28: ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ cell energy electron lamp. Coulomb of charge (electrons) Think of it as a “bag of electrons” (containing 6250000000000000000 electrons!)

Voltage (p.d.)☺

☺☺

☺☺☺

V

I’m checking the difference in energy (per

coulomb) before and after the lamp

1 Volt = 1 Joule per coulomb

Page 29: ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ cell energy electron lamp. Coulomb of charge (electrons) Think of it as a “bag of electrons” (containing 6250000000000000000 electrons!)

Voltage

Voltage is the amount of energy transferred (changed) per coulomb of charge.

1 Volt = 1 Joule per coulomb

A voltmeter connected across the component

Page 30: ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ cell energy electron lamp. Coulomb of charge (electrons) Think of it as a “bag of electrons” (containing 6250000000000000000 electrons!)

In a series circuitThe sum of the voltages across the lamps

equals the voltage across the cells

9 V

3 V 3 V 3 V

Page 31: ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ cell energy electron lamp. Coulomb of charge (electrons) Think of it as a “bag of electrons” (containing 6250000000000000000 electrons!)

In a parallel circuitIn a simple parallel circuit, voltage across each lamp equals the voltage across the cells

5 V

5 V

5 V

Page 32: ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ cell energy electron lamp. Coulomb of charge (electrons) Think of it as a “bag of electrons” (containing 6250000000000000000 electrons!)

Resistance

Measures how difficult it is for current to flow. Measured in Ohms (Ω)

VA

Resistance = voltage/current R = V/I

Page 33: ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ cell energy electron lamp. Coulomb of charge (electrons) Think of it as a “bag of electrons” (containing 6250000000000000000 electrons!)

Ohm’s Law

• V = IR

V

RI X

Page 34: ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ cell energy electron lamp. Coulomb of charge (electrons) Think of it as a “bag of electrons” (containing 6250000000000000000 electrons!)

Resistance of a lamp

AV

Resistance = voltage/current R = V/I

Vary the voltage and current using a variable resistor (rheostat). Plot a graph of resistance against current

Page 35: ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ cell energy electron lamp. Coulomb of charge (electrons) Think of it as a “bag of electrons” (containing 6250000000000000000 electrons!)

Power

The amount of energy used by a device per second, measured in Watts (Joules per second)

VA

Power = voltage x current P = VI

Page 36: ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ cell energy electron lamp. Coulomb of charge (electrons) Think of it as a “bag of electrons” (containing 6250000000000000000 electrons!)

Example

• A 200 W television is plugged into the 110V mains. What is the current in the television?

• I = P/V = 200/110 = 1.8A

PIV X

Page 37: ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ cell energy electron lamp. Coulomb of charge (electrons) Think of it as a “bag of electrons” (containing 6250000000000000000 electrons!)

Total energy

So the total energy transformed by a lamp is the power (J/s) times the time the lamp is on for in seconds,

E = VItE = energy transformed (J)

V = Voltage (also called p.d.)

I = current (A)

t = time (s)

Page 38: ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ cell energy electron lamp. Coulomb of charge (electrons) Think of it as a “bag of electrons” (containing 6250000000000000000 electrons!)

Example

• A kettle uses 240V and 8A. What is its power?

• P = VI = 240x8 = 1920W (=1.9kW)

• How much energy does the kettle use in 5 minutes?

• E = VIt = 240x8x300 = 576000 J PIV X

Page 39: ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ cell energy electron lamp. Coulomb of charge (electrons) Think of it as a “bag of electrons” (containing 6250000000000000000 electrons!)

Alternating current

• Current changes direction 50 times a second.

Page 40: ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ cell energy electron lamp. Coulomb of charge (electrons) Think of it as a “bag of electrons” (containing 6250000000000000000 electrons!)

Fuse

• Thin piece of wire which melts if the current is too high

• If a fault develops, this thin piece of wire melts if the current is too high

• Circuit breakers are sometimes used instead

Page 41: ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ cell energy electron lamp. Coulomb of charge (electrons) Think of it as a “bag of electrons” (containing 6250000000000000000 electrons!)

Earth wire

• Connects metal body of appliance to earth

• If a live wire comes loose, current flows to earth and blows the fuse

Page 42: ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ cell energy electron lamp. Coulomb of charge (electrons) Think of it as a “bag of electrons” (containing 6250000000000000000 electrons!)

Double insulation

• Some appliances have no earth wire because they have a plastic outer case

• The plastic case acts as an extra layer of insulation around the wires

Page 43: ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ cell energy electron lamp. Coulomb of charge (electrons) Think of it as a “bag of electrons” (containing 6250000000000000000 electrons!)

Electrostatics

1. There are two types of electric charge (positive and negative)

Hi! Hola!

Page 44: ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ cell energy electron lamp. Coulomb of charge (electrons) Think of it as a “bag of electrons” (containing 6250000000000000000 electrons!)

Electrostatics

2. Opposites attract

Page 45: ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ cell energy electron lamp. Coulomb of charge (electrons) Think of it as a “bag of electrons” (containing 6250000000000000000 electrons!)

Electrostatics

3. Static charges can be produced by the action of friction on an insulator

Plastic, amber, glass, Perspex

Page 46: ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ cell energy electron lamp. Coulomb of charge (electrons) Think of it as a “bag of electrons” (containing 6250000000000000000 electrons!)

Electrostatics

4. Electrons are negatively charged

Page 47: ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ cell energy electron lamp. Coulomb of charge (electrons) Think of it as a “bag of electrons” (containing 6250000000000000000 electrons!)

Electrostaticshttp://phet.colorado.edu/sims/balloons/balloons_en.jnlp

5. Objects are charged positive by the loss of electrons

cloth

Page 48: ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ cell energy electron lamp. Coulomb of charge (electrons) Think of it as a “bag of electrons” (containing 6250000000000000000 electrons!)

Electrostatics

6. Objects are charged negative by the gain of electrons

Only electrons move, that’s why they call it

electricity!cloth

Page 49: ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ cell energy electron lamp. Coulomb of charge (electrons) Think of it as a “bag of electrons” (containing 6250000000000000000 electrons!)

ElectrostaticsYouTube - Refueling Fire Caused by Static Electricity

7. Static charges can be dangerous

Page 50: ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ cell energy electron lamp. Coulomb of charge (electrons) Think of it as a “bag of electrons” (containing 6250000000000000000 electrons!)

Electrostatics

7. Static charges can be dangerousYouTube - Gas Station Fire, Static Electricity Starts a Flash Fire.

Page 51: ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ cell energy electron lamp. Coulomb of charge (electrons) Think of it as a “bag of electrons” (containing 6250000000000000000 electrons!)

Electrostatics

8. Static charges can be useful

Page 52: ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ cell energy electron lamp. Coulomb of charge (electrons) Think of it as a “bag of electrons” (containing 6250000000000000000 electrons!)

Electrostatics

8. Static charges can be useful

Page 53: ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ cell energy electron lamp. Coulomb of charge (electrons) Think of it as a “bag of electrons” (containing 6250000000000000000 electrons!)

ElectrostaticsYouTube - Bill Nye the Science Guy - 25: Static Electricity 1/3

YouTube - Mitsuba Systems - Sprayright Series 700 Powder Spray System

8. Static charges can be useful

Page 54: ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ cell energy electron lamp. Coulomb of charge (electrons) Think of it as a “bag of electrons” (containing 6250000000000000000 electrons!)

Draw the sentence

1. There are positive and negative charges

2. Opposite charges attract and like charges repel

3. Static charges can be made by the action of friction on an insulating material

4. Electrons are negatively charged

5. Objects are charged positively by the removal of electrons

6. Objects are charged negatively by the addition of electrons

7. Static electricity can be dangerous (aeroplane refueling and gas stations)

8. Static electricity can be useful (painting, photocopiers and removal of smoke from chimneys)