Physics - Electromagnetic Waves + More Flashcards
What 4 things are electromagnetic waves?
- ? waves that can travel through a ?
- consist of vibrating and ? field
- travel at same ? in a vacuum, ? m/s
- Transfer ? from a source until ?
transverse, vaccum,
magnetic,
speed, 300,000,000,
energy, absorbed
on the visible spectrum where is the wavelength highest?
red
on the visible spectrum where is the frequency highest?
violet
atomic changes lead to electromagnetic waves being produced , give two examples of this:
-arrangement of electrons
- radioactive nuclei decay giving off particles, and a subsequent release of energy in the form of a gamma
Radio waves production -
are made by oscillating ?, these currents flow in the ? aerial, which cause oscillating electric and ? fields to be created - an ? field
electrons, transmitting, magnetic, electromagnetic
What are radio waves used in?
comma - radio and TV signals as well as satellite comms
what are the 3 different types of radio waves and what are their lengths they can travel
long - (10-20km), short/medium (1-10km), FM and TV (10cm -10m)
Satellite comms - what does their long wavelength enable them to do?
pass through the earths atmosphere without being refracted or absorbed
how do microwaves work?
water molecules absorb the ? in the microwave ? - then transferring the ? energy to the thermal ? store of the food
micro waves, oven, waves’, energy
what is a black body?
an object that absorbs all the radiation it receives and emits all types of radiation
what does a blackbody not do?
transmit or reflect any radiation/wavelengths of light
what do hotter bodies have?
greater amount of radiation per second
greater amount of short wave radiation released
As temperature increases in a blackbody what happens?
the intensity of every ? wavelength increased, the ? the wavelength the more rapid the ? in intensity, the peak ? occurs at ? wavelength
emitted, shorter, rise, intensity, shorter
why are all objects continuously emitting electromagnetic radiation?
due to the energy in their thermal stores
the radiation is of a ? range of wavelengths across the ? spectrum. the amount of type/? of radiation depends on the object’s?
wide, electromagnetic, intensity, temperature
which type of electromagnetic wave has the highest intensity?
visible light
electromagnetic spectrum going from longest wavelengths to highest frequency
radio waves —> microwaves —> infrared —> visible light —> ultraviolet —> x-ray —> gamma ray
definition of reflection
change in direction of a wavefront between 2 different media (plural of medium)
what is speculation reflection - what surface and reflection?
a smooth surface and single/normal reflection
what is diffuse reflection - what surface and type of reflection?
rough surface, and causes scattering
definition of absorption
process in which light is transferred to energy within a material
definition of transmission?
when light passes through a material without being reflected or absorbed
definition of opaque?
a material that does not transmit light (but does absorb and reflect it)
definition of transparent??
a material that allows light to pass through without being scattered, eg : a window