Flashcards in Physics Deck (38):
What are longitudinal waves
That particles vibrate back and forth, so the direction of their movement is parallel to the direction of the wave eg sound waves
What is a transverse wave
In a a transverse wave, the particles move up and down so the direction of their movement is at right angles to the direction of the wave eg water and light waves
What is frequency
Frequency is the number of waves passing any point each second
What is current
Current is a measure of the rate of flow of electric charge in a circuit
How much is there
What is current measured in
What is another name of potential difference
It is the same as voltage
What is potential difference
Potential difference is a measure of the different in electrical potential energy between two points in a circuit
What is voltage measured in
Volts using a voltmeter
What is a cell
A cell is an individual
What is a battery
More than one cell
The greater the electrical action demands....
The greater the current needed
Using more cells in a battery....
Increases the voltage
What is a series circuit
A series circuit has all of the components connected sequentially in a “loop”. If one part breaks the whole circuit will stop working.
What is a parallel circuit
A parallel circuit is a “branched circuit”. Meaning is has two ways for electricity to flow through. A break will stop that particular “break” from working. If their is a alternate complete path, then the electricity will flow through it.
What happens if you put soothing in a glass of water and look through the glass at it. Why does it look different?
The light has been refracted because it’s travelling through a different medium and is being slowed down by that particular medium therefor making the object appear different
What is a particle model
A model that can be used to explain the properties of solids, liquids and gases. In a solid the particles are packed closely together, the particles vibrate on the spot but hold shape. In a liquid the particles are packed closely together too but they are free to move and flow over each other. Particles in gases are not bound together at all and are free to move in a straight line until they hit another particle.
Define and insulator and compare it to a conductor
An insulator is a material that does not conduct heat well where as a conductor allows heat to flow through it. Ex of insulator, air, cloth, cork. Ex of conductors, metal
What is a sound wave
A sound wave is the movement of alternating compressions and rarefactions
What are compressions and rarefactions?
Compressions is a region of high pressure in which particles are close together and rarefaction is a region of low pressure in which particles are far apart
What is an electromagnetic wave
Transverse electric and magnetic fields position at right angles to each other and travelling through empty space at the speed of light
What electromagnetic radiation
Electromagnetic waves consisting of oscullating electric and magnetic fields travelling at the speed of light
Label and draw a diagram of a wave
Compare frequency and pitch
Frequency is the number of waves passing any point
Each second (measured in hertz) whereas pitch is how low or high
A sound is. A source that vibrates rapidly creates a higher pitch sound than one that vibrates slowly.
Examples of radiation, convection and conduction
Radiation: the sun
Convection: boiling water or heating a room using a fireplace
Conduction: hot liquids make the cup itself hot or holding an ice cube
How is energy transferred through conduction and is it a particle or wave
particles in hot things vibrate faster so when something touches the heat, the particles start vibrating faster too.
A method of heat transfer in which heat is passed by vibration of particles.
It is a particle transfer
How is energy transferred through convection, particle or wave?
as the air is heated the particles gain energy and rise as the cool air sinks. As the cool air sinks it is heated by the heat source and rises leaving the cool air to be heated. This type of jets transfer can only happen in liquid and gases are their particles can move.
transfer of heat in liquid or gas due to less dense, warmer matter rising and dense, cooler matter falling
How is energy transferred through radiation
Particle or wave?
radiation transmits waves through invisible electromagnetic waves that travel at the speed of light, everything gives off infrared radiation, the hotter the object the more radiation
movement of heat in the form of electromagnetic waves, which can travel through a vacuum
How is energy transferred through sound
Wave or particle
Sound is created when something vibrates. When something vibrates it passes it vibrations into its surroundings. Sound waves travel away from the spice of sound (ripples in a lake)
The particles of the material vibrate as the sound energy flows through it.
It travels faster through solids than through gases as the particles are closer together transmitting the energy faster as they have less distance to travel to the next particle
Sound travels faster through warm things than cold things as the particles in warm things are already vibrating
What is refraction
Refraction is bending of light as it passes from one substance into another substance
Light travels at different speed through difference substances, the difference in the speed results in different amounts of bending
How does a concave lens work
A concave lens’s is a lens that curves inwards
When parallel rays of light pass through a concave lens the refracted rays diverge so they appear to come from one point called the principle focus
A convex lens bulges outwards
What is the electromagnetic spectrum
The entire range of frequencies of electromagnetic radiation that can be produced, from high frequencies gamma rays to low frequency radio waves.
What does an electric circuit need
An energy source (cell, battery)
An energy user (bulb, light)
Wires to connect everything
What is the order of the electromagnetic spectrum
Ultra violet radiation
What is resistance
A measure of how difficult it is for current to pass
What is resistance measured in
Ohms (the thing that looks like a horse shoe)
How does energy transfer through a circuit
light the flow of charge is made up of electrons moving along the wires. These electrons and the current they form, carry energy around the circuit from the battery or power point, to the different components that use it . All electrons flow along the circuit in the same direction.
Why does voltage drop when a wire is small and long
the resistance of a long wire is greater than the resistance of a short wire because electrons collide with ions more often. The resistance of a a thin wire is greater the resistance of a thick wire because a thin wire has fewer electrons to carry the current.