Physics Flashcards
Describe a longitudinal wave and tranverse wave and how they differ
Transverse: occilate up and down, at right angles to the direction of energy transfer
Longitudinal: ocilate by a series of comression and rarefractions that transfers energy parrallel with the direction
Draw a labelled diagram of a wave
need to include:
-amplitude
-wavefront
-wavelength
How do transverse and longitudinal waves differ in vacuums
transverse: Can (electromagnetic waves
longitudinal: cannot
How do transverse and longitudinal waves differ in vacuums
transverse: Can (electromagnetic waves
longitudinal: cannot
How do transverse and longitudinal waves differ travelling in different materials
Transverse: can travel through solids, and on surface of liquids
Longitudinal: can travel through all matter
Define frequency
number of waves passing a certain point per second
define time period
Amount of time taken for a single wave to pass a point
wave transfer _________ without transferring _______
energy and info
matter
wave speed =
frequency x wavelength
v = f x λ
Whats the frequency range for human hearing
20Hz - 20,000Hz
How do you measure the speed of sound in air?
Clap-echo method.
measure the time taken for you to hear an echo from a sharp clap, either made by hands or by banging two wooden blocks together.
You stand a long distance from someone, they clap, and listen for the echo
(time jhow long it takes and then do the equation)
—>speed=distance/time
How are pitch and volume worked out when looking at a wave graph
pitch - frequency
volume - amplitude
What is current
the rate of flow of charge
What does charge equal
charge = current x time
How does electrical current flow in solid metal conductors
Its the flow of negitively charged electrons, and is a conductor because the electons are free to move between atoms
Give 5 examples of electrical conductors:
Copper, Brass, Steel, Gold, and Aluminium
—>these are used in wires
(mercury is a very good liquid conductor)
Give 5 examples of electrical insulators:
Plastic, wood, glass and rubber
—>used to cover electrical conductors
Give 5 examples of electrical insulators:
Plastic, wood, glass and rubber
—>used to cover electrical conductors
Describe the investigation that tests the transfer of electrical charges on insulaters and what the observations will be
Take a polythene rod, hold it at its centre and rub both ends with a cloth and suspend the rod, without touching the ends
Take an acrylic rod and rub it with another cloth
Bring each end of the acrylic rod up to, but without touching, each end of the polythene rod
Record any observations of the polythene rod’s motion, repeat, changing out the acrylic rod for rods of different materials
When two insulating materials are rubbed together, electrons will transfer from one insulator onto the other insulator
—>A polythene rod is given a negative charge by rubbing it with the cloth
—>This is because electrons are transferred to the polythene from the cloth and electrons are negatively charged, hence the polythene rod becomes negatively charged
Conversely, an acetate rod is given a positive when rubbed with a cloth
—>This is because electrons are transferred away from the acetate to the cloth, so loses negative charge and becomes positive
Like charges ______
Oppossite charges ______
repel
attract
Like charges ______
Oppossite charges ______
repel
attract
What are the dangers of electrostatic
Sparks
