electromagnetic radiation Flashcards
(20 cards)
radiation
transmission of energy in the form of wave or particles through space or a material medium
electromagnetic radiation eg
radio waves, microwaves
particle radiation eg
alpha, beta and neutron radiation
acoustic radiation eg
ultrasound, sound and seismic waves
gravitational radiation eg
takes the from of gravitational waves or ripples in the curvature of spacetime.
properties of EM radiation
- energy carried by waves appears in several forms : heat, sound, light, x-rays
- all waves are carried by some form of oscillation eg EM by electric and magnetic fields
oscillation
repetitive varieties of some about a central value
what term is used to describe mechanical oscillation?
vibration
two types of waves
longitudinal + transverse
longitudinal
- requires a medium through which to travel, particles of the transmitting medium are displaced along the direction of propagation
transverse
don’t always require a medium to travel, energy is travelling at right angles to the direction of the oscillation
amplitude
largest displacement encountered during the oscillation
wavelength
distance between two consecutive points
period
an oscillation is the the time taken to complete one cycle
frequency
number of cycles completed every second
rectilinear propagation
EM waves travel in straight lines
radiation intensity
quantity of radiation energy passing through a unit area per unit of time
wave particle duality
EM radiation behaves like waves, however if compromised behaves in discrete packets of energy called quanta which are pure energy.
electric current
net charge flowing through any point of wire per unit time
potential difference
the work done per unit charge passing between the points
