Polarisation
What is the polarisation of an EM wave
Polarisation refers to the orientation of the electric field vector of an EM wave in a specific direction
How is polarisation used in sunglasses?
Polarised sunglasses reduce glare by blocking horizontally polarised light, which is commonly reflected off surface like water or roads.
What is linear polarisation?
In linear polarisation, the electric field vector oscillates in a single, fixed direction as the wave propagates
What role does polarization play in communication systems?
In communication systems, polarization is used to transmit multiple signals over the same frequency band without interference by using different polarization states.
How does polarisers work?
A polariser allows only EM wave oscillating in a specific direction to pass through while blocking waves with other polarisation directions.
How do antennas transmit polarized EM waves?
The polarisation of the wave radiated by an antenna depends on the geometry of the antenna. A dipole antenna, for instance, radiates linearly polarised waves along its axis.
What causes EM waves to become polarized?
EM waves can become polarised due to reflection, refraction, scattering or transmission through a polarizing medium.
Satelite dishes in Europe need to point south, explain why?
The satellites orbit the Earth directly above the equator
What is Malus's Law?
Malus's Law states that the intensity of polarised light passing through a polariser is proportional to the square of the cosine of the angle between the light's polarisation direction and the polariser's axis.
Link the size of dish to diffraction
The bigger dish diffracts the waves less.