TIR And Lenses Flashcards
State the equation used to calculate intensity
I=P/A
What is the refractive index of a material through which light travels a speed of v
N=c/v
State the equation linking the refractive indexes and angles at an interface between two mediums
N1sinø1=n2sinø2
What is the critical angle
The angle of incidence for which the angle of refraction is 90° and all the light passes along the boundary between the mediums. Beyond this angle all light will be reflective
State the equation used to calculate the critical angle
SinC=1/n
What is total internal reflection
Total internal reflection is where all the light is reflected back at the boundary between two mediums. It occurs when light is incident at an angle greater than the critical angle
What is the focal point of a converging lens
The single point where the parallel rays of light entering the lens coverage to
What is the focal length of a lens
The distance between the centre of the lens and the focal point
What is the equation used to calculate the power of a pense
Power =1/focal length
How do you calculate the total power of a combination of thin lenses
P=P1+P2+P3…
What is a real image
A real image is one that can be projected onto a screen and is always inverted. Real images are the consequence of light meeting at a focal point
What is a virtual image
Virtual images are the consequence of rays of light appearing to meet at a point. They cannot be projected onto a screen
State the equation used to calculate the magnification of an image
Magnification =image height/object height
What is plane polarisation
Plane polarisation is when the oscillations of a wave are restricted to a single plane
