# Unit 2: Electricity

• Created by: tdicks
• Created on: 24-11-18 15:11
• Electrons
• Power
• Voltage
• Resistance
• in parallel
• resistance is less than the smallest resistance value
• because a larger amount of electrons flow through the circuit
• in series
• R = r1+r2+r3
• because electrons make more collisions
• depends on ...
• length of wire
• REQUIRED PRACTICAL
• light intensity
• temperature
• I/V graphs
• wire resistor
• DIAGONAL
• as V increases
• resistance is constant
• resistance = 1/gradient
• Untitled
• resistance increases
• because temperature of filament increases
• electrons collide more and vibrate with positive ions
• V is directly proportional to I
• ohmic conductor
• Untitled
• Untitled
• filament lamp
• S SHAPE
• as V increases
• resistance is constant
• resistance = 1/gradient
• Untitled
• resistance increases
• because temperature of filament increases
• electrons collide more and vibrate with positive ions
• V is directly proportional to I
• ohmic conductor
• Untitled
• Untitled
• LED
• LINE, UP
• required practical
• R = V/I
• V = voltage
• measured in volts
• I = current
• measured in amps
• R = resistance
• measured in ohms
• Current
• ammeter connected in series
• resistance very small
• doesnt reduce current
• always the same current
• because charge is reserved
• current leaving cell is current entering cell
• because charge is reserved
• sum of current in parallel are branches added up
• I = Q/t
• I = current
• measured in amps
• Q = Charge
• measured in coulombs
• t = time
• measured in seconds
• electron flow is ac
• 230 mains voltage
• provided by power station
• step up transformer connected
• reduces current in overhead cables
• step down transformer connected
• reduces voltage
• step down transformer connected
• reduces voltage
• increases voltage
• 3 pin plug
• case
• plastic
• insulator
• wires
• copper
• conductor
• earth wire
• green and yellow stripes
• 0 volts
• carrries current if there's a fault
• prevents appliance becoming live
• neutral wire
• blue
• 0 volts
• carries current back to source
• prevents user getting an electric shock
• live wire
• brown
• 230 volts
• contains a switch
• very dangerous
• contains
• 2 cores
• live and neutral
• 3 cores
• live, neutral and earth
• flow reverses 50 times per second
• 50 Hz
• electron flow in one direction is direct current
• provided be cells and batteries
• contain chemical energy stores
• Electrostatic Charge
• when you gain electrons, you gain negative isulator charge
• eg. brushed hair stands on end
• when you loose electrons, you gain positive insulator charge
• Electrostatic Charge
• when you gain electrons, you gain negative isulator charge
• eg. brushed hair stands on end
• when you loose electrons, you gain positive insulator charge
• eg. brushed hair is attracted to brush
• force at a distance is a non-contact force
• force is experienced at an electric field
• point charge is radial
• ARROWS OUTWARDS
• repulsive charge on a positive charge
• force decreases as distance from charge increases
• arrows show direction of force on a positive charge
• ARROWS OUTWARDS
• repulsive charge on a positive charge
• force decreases as distance from charge increases
• ARROWS INWARDS
• attractive charge on a positive charge
• ARROWS INWARDS
• attractive charge on a positive charge
• causes sparking between charged object and earth
• when force on air icles is large enough to ionise air
• so electrons are transferred between charged object and earth
• eg. brushed hair is attracted to brush
• force at a distance is a non-contact force
• force is experienced at an electric field
• point charge is radial
• arrows show direction of force on a positive charge
• causes sparking between charged object and earth
• when force on air icles is large enough to ionise air
• so electrons are transferred between charged object and earth

## Comments

No comments have yet been made

## Similar Physics resources:

See all Physics resources »See all Electricity resources »