Rest of Notes Flashcards
What is static electricity?
Static electricity is a build-up of electrical charge on an object.
What happens when you rub one neutral , electrically insulating object against another?
Some of the electrons are transferred across. This leaves an excess of negative charge on one of the objects, and a deficit on the other.
Outer insulation
All three wires in the cable are bundled together and there is extra plastic insulation wrapped round them all for safety
Cable grip
This holds the cable tightly in place so that wires do not become loose
Live wire
Copper wire coated with brown plastic along which the current enters the device
Fuse
A glass or ceramic canister containing a thin wire that melts if the current gets too high
Neutral wire
Copper wire coated with blue plastic that also connects to the cable in the wall and completes the circuit
Earth wire
Copper wire coated in striped plastic that provides a path for current to flow from the case of the device to the ground if there is a fault
what does energy =
energy=power x time
What is the unit for charge?
Coloumbs
What is the unit for resistance?
Ohms
What is the unit for potential difference?
Volt
What is the unit for current?
Ampere
What is a renewable energy resource?
Renewable energy is energy that comes from a source that won’t run out. .
What are examples of renewable energy resources?
Examples of renewable energy sources include wind power, solar power, bioenergy (organic matter burned as a fuel) and hydroelectric, including tidal energy.
What is a non renewable energy resource?
An energy resource that can run out.
What are examples of non renewable energy resources?
Coal,oil and natural gas.
what is the independent variable?
Independent variable – the variable that is altered during a scientific experiment.
What is the dependent variable?
Dependent variable – the variable being tested or measured during a scientific experiment.
What is the control variable?
Controlled variable – a variable that is kept the same during a scientific experiment.
What are the types of waves?
Transverse
Longitudinal
Mechanical
Electromagnetic
What do waves do?
They transfer energy without transferring matter.
Transverse?
The vibrations are perpendicular to direction of energy transfer.
Longitudinal?
The vibrations are parallel to the direction of energy transfer.
What is a transverse wave that is mechanical?
Water waves
What is a transverse wave that is electromagnetic?
Light wave
What is a longitudinal wave that is mechanical?
Sound waves.
What is a longitudinal wave that is electromagnetic?
Earthquake wave.
What is the amplitude?
The maximum distance from the undisturbed position.
What is the wavelength?
The distance between the point on a wave to the same point on another wave eg ( crest to crest) or (trough to trough)
What is the compression of wave?
The compression of a wave is an area of higher pressure and the particles are more densley packed.
What is the rarefaction of a wave?
The rarefaction is an area of lower pressure and the particles are less densely packed.
What is the frequency?
The frequency of a wave is the number of waves produced by a source each second.
Features of reflection?
1 No change in frequency
2 No change in wavelength
3 No change in speed
4 Direction of wave travel changes.
