Exam Revision Flashcards
1
Q
Conditions for Circular Polarised Light
A
- Ez has a phase difference of π/2
- Ez and Ey have same magnitude
- Negative Phase difference - Right circular polarised
- Positive Phase difference - Left circular polarised
2
Q
Conditions for Linear Polarised Light
A
- Ez has a phase difference of 0 or π
- Ez and Ey have different magnitude
- Positive Phase difference - Horizontally polarised
- Negative Phase difference - Vertically polarised
3
Q
Relation between Magnetic Field and Electric Field
A
- They are perpendicular
- B * E = c
4
Q
Circular Polarised Light Definition
A
- A transverse wave where the E field rotates around direction of travel
- E field is perpendicular to the direction of travel
- Rotates either clockwise or anticlockwise
5
Q
Polarisation Angle definition
A
Angle of incidence at which polarised light is transmitted through a surface with no reflection
6
Q
Unpolarised light hits a surface at the polarisation angle
A
Reflected light is perfectly polarised
7
Q
Wave reflecting at a fixed end
A
- The wave will be reflected and inverted
- Boundary Condition - y=0 at the end
8
Q
Wave reflecting at free end
A
- Reflects the wave without inverting
9
Q
Two Strings joined together with different μ values
A
- Tension is same in both strings
- Frequency is same in both strings
- Use equations to find speed and wavelength
10
Q
Impedance of a string equation
A
Z^2 = μT
11
Q
Observations if μ1 < μ2
A
- Wave is transmitted
- Reflected wave is inverted
12
Q
Observations if μ1 > μ2
A
- Wave is transmitted
- Reflected wave is not inverted
13
Q
Observations if μ1 = μ2
A
- Wave is transmitted
- No reflected wave
14
Q
Transmission Coefficient Equation for 2 strings
A
t = 2Z1/(Z1 + Z2)
15
Q
Reflection Coefficient Equation for 2 strings
A
r = (Z1 - Z2) / (Z1 + Z2)
