Defintions Flashcards
Amplitude
The measure is the displacement of a wave from its rest point, the higher the amplitude of a wave and he higher its energy.
Crest
The crest of a wave is its highest point
Diffraction
Diffraction is when a wave remains in the same medium, but bends around an object
Electromagnetic Wave
Electromagnetic waves are waves that can travel through a vacuum. E.g. Light. They do not need a medium
Frequency
The frequency of a wave is the number of times per second the wave cycles. The frequency is the inverse of a period.
Interference
Interference is when one wave comes into contact with another wave
Light wave
A light wave is a special type of electromagnetic wave that has a frequency in the light spectrum
Longitudinal waves
A wave in which the vibration is in the same direction that the wave is travelling
Medium
A medium is matter that a wave travels through. (Anything with particles) e.g. Solid, Liquid or Gas
Transparent
Light passes through easily and objects can be seen clearly
Translucent
Allows light to pass through but objects aren’t detailed, mixed up
Opaque
Light can’t pass through and is either reflected or absorbed into the substance
Regular Reflection
When light reflects off a very smooth surface such as a mirror or a window
Diffuse reflection
When light reflects off a rough surface the light reflects in many direction ps and doesn’t form a clear image
Refraction
Refraction is where light bends through different mediums
Law of reflection
The law states that the angle of incidence and the angle of reflection are equal
Lateral inversion
Image is identical to the object in every way except that it is reversed sideways
Ray diagram
A ray diagram is a drawing of the light rays coming from a mirror and light source, with the reflections and labels
Law of refraction
If a ray travels form a less dense medium to a denser medium it bends towards the medium. Or when a ray travels from a denser medium to a less dense medium it bends away from the normal
Absolute zero
The lowest possible temperature; -273c
Conduction
A method of heat transfer in which heat is passed through a solid object by the vibration of particles.
Conductor
A substance that allows heat to flow through it
Convection
A method of heat transfer where a gas or liquid flows. Where a less dense substance warms up and flows upwards then cools and falls.
Insulator
A material that does not conduct heat
Radiation
Movement of heat in a form of electromagnetic waves, results in how hot or cold an object is, e.g the heat from the sun on earth. Doesn’t need a medium to travel through unlike conduction and convection
Temperature
A measure of the average kinetic energy of particles in a substance that results in how hot or cold the object is
Heat
Heat is a form of kinetic energy measured in kilojoules
SONAR
Sound, Navigation and Ranging
Ultrasound
Higher than 20,000 Hz
Infrasound
Lower than the human hearing range
Infra and Ultra (light)
Infra - below visible light on the spectrum
Ultra - above visible light on the spectrum
