Electricity Investigation Flashcards
what does Sonar stand for
SOund Navigation And Ranging
Use fo Sonar
Used to locate and detect shipwrecks and fish. Uses high frequency noises. Works by measuring time taken for noises to echo back to ship.
Echolocation
Used by animals to find prey and detect surroundings
Name the spectrums of the electromagnetic spectrum in order
Radio waves Infrared radiation Visible light Ultraviolet radiation X-rays Gamma rays Electromagnetic waves
Radio waves
Low energy waves
Used to communicate over long distances
Infra-red radiation
Created by all objects and sensed as heat
Visible light
Visible
Plants cant photosynthesis without it
Travels at 300 000 kilometres per second
Ultraviolet radiation
Needed by body to make vitamin D
X-rays
Enough energy to pass through flesh.
Produced when fast-moving electrons give up energy quickly. Happens when electrons hit a target made of tungsten
Gamma rays
Used to kill cancer cells and find weakness in metal.
Electromagnetic waves
Waves travel through air at 300 000 000m/s. Can travel in a vacuum.
Waves consist of repeating pattern of electric and magnetic forces, forces generated by by changes in speed/direction of moving electric charge
3 possible situations when light comes in contact with an object
Reflection, pass through, absorbed
Reflection
Light bounces off surface
Luminous
Produces own light
Scattering
Light reflects when inside the object
Transparent
Object where light can pass through
Translucent
Some light passes through but not all
Opaque
No light can pass through material
3 types of mirrors
Plain - straight
Concave - curved in
Convex - curved out
Law of reflection
Light is reflected of surface at same angle it bounced onto
Focal point
When parallel rays bounce of concave or convex mirror, their intersection point is known as the focal point
Lateral inversion
Sideways reversal of images they you se when you look in a mirror
Refraction
When light travels from a denser or less dense medium into another medium it bends
Image
Picture seen in mirror or water
Electric circuit
Pathway in which electricity passes through
Static electricity
Doesn’t move
Only moves when enough has built up.
3 essentials in electric circuits
Power supply
Load
Conductive path
Power supply
Provides the electrical energy
Load
Where electrical energy is converted to useful forms of energy
Conductive path
Allows electric charge to flow around the circuit
How batteries work
Stores chemical energy and is released into electrical energy when chemical reaction takes place
Electric current
Flow of electric charge
Measure of amount of electric charge passing a particular point in circuit every second.
Defined as direction of movement of positive charge. Current caused by negatively charged energy
Voltage
Measure of amount of electrical energy gained or lost by electrical charge as it moves through circuit.
2 types of circuits
Parallel
Series
Parallel circuit
Each component is connected in seperate conductive path.
Same voltage all around the circuit, current different all around
Series circuit
Power supply, load and conductive path all in line
Same current all round the circuit, different voltage all round
2 factors affecting speed of energy flow
Amount of energy each electron has.
Number of electrons passing through the globe every second
Electrical insulator
Has a large energy resistence
Factors affecting resistance
Type of material
Length of wire
Diameter or thickness of the wire
Temperature of the wire
Resistance
Measure of how difficult it is for electrons to flow through part of a circuit.
Variable resistor
Device in which resistance can be affected
What is the electromagnetic spectrum
Range of wavelengths over which electromagnetic radiation extends
