Waves and Optical Fibres Flashcards
What are the two types of waves?
Transverse and Longitudinal waves
What are examples of transverse waves?
Water waves, Seismic S waves, all Electromagnetic waves
What are examples of longitudinal waves?
Sound waves, Seismic P waves
What is the amplitude?
The maximum disturbance of a wave from its rest
What is the wavelength?
The distance between a point on one wave and the same point on the next
What is the crest?
The peak of the wave
What is the trough?
The bottom of the wave
What is frequency measured in?
Hertz (Hz). one hz is one wave per second
What is frequency?
The number of cycles of a wave per second
What are the 4 layers of Earth? (in order)
Crust, Mantle, Outer core, Inner core
List properties of P waves
They are longitudinal waves, their relative speed is faster than regular waves, they can travel through solids and liquids
List properties of S waves
They are transverse waves, they are slower than P waves and can only travel through solids
What are the 3 types of Seismic waves?
Surface waves, P waves and S waves
What causes the light to be refracted in TIR?
The speed of the light changes because of the change in density
When light goes from a more dense to less dense area, which angle is greater?
Refraction angle
What is the critical angle?
When the angle of refraction is 90 degrees
What is glass’ critical angle?
42 degrees
What happens when the angle is greater than the critical angle?
The light will become totally internally refracted and will stay inside the glass, turning back on itself
How do optical fibres function?
With total internal reflection
What is an optical fibre and what is it used for?
A thin rod of high quality glass used to transmit light and data at a high speed
What is an endoscope?
Optical fibres which are inserted into the body showing a 2D image for the doctor
What is a CT scan?
A use of X-rays to present a 3D image of the body
Which is less harmful, endoscopy or CT scans? Why?
Endoscopy is less harmful because it uses light instead of X-rays
How do you calculate time delay?
Distance divided by speed of light
How do you calculate speed of light?
Distance divided by time delay
How do you calculate distance?
Time delay multiplied by speed of light
