Physics P1 Flashcards
what do you know about the speed of electromagnetic waves?
It is constant and equal to the speed of light
electromagnetic wave
a wave that propagates when an electric field oscillating in one plane produces a magnetic field oscillating in a plane at right angles to it
why are electromagnetic waves classified as transverse waves?
The changing electric and magnetic fields oscillate at right angles to the diretion the wave is travelling
EM spectrum (increasing frequency)
radio waves, microwaves, infrared rays, visible light, UV rays, X-rays, gamma rays
ionising radiation
electromagnetic waves that have enough energy to break chemical bonds and form ions
one photon
A quantum (energy packet) of light
wave-particle duality of EM radiation
light has wave-like and particle-like properties
how are elecromagnetic waves formed?
Oscilating charges speed up and slow down, causing a changing electric field which produces a changing magnetic field. The process is self propagating
principle of charge quantization
all chaarges consist of an integer multiple of the charge of single electron (Q=nqe)
principle of conservation of charge
the charge of an isolated system remains constant during any physical process
distance vs displacement
the total path length travelled vs the overall change in position of an object
pulse
single disturbance that moves through a medium
wave
a regular succession of pulses
transverse wave
particles oscillate at right angles to the direction of motion of the wave
longitudinal wave
particles oscillate parallel to the direction of motion of the wave
principle of superposition
when two or more pulses meet, the resultant is the algebraic sum of their amplitudes
constructive interference
the crest of one pulse overlaps ith the crest of another increasing amplitude
destructive interference
crest of one pulse overlaps with the trough of another decreasing amplitude
wavelength
distance between two successive points on a wave that are in phase
amplitude
position of maximum displacement from equilibrium position
frequency
number of waves passing a point per second
period
time taken for one wave to pass a point
gravitational potential energy
the energy that an object has because of its position relative to a reference point
law of conservation of energy
the total energy of an isolated sysem remains constant