Optics Test 1
Visible light wavelength is approximately __________ to _________.
400 - 700 nm (10^-9m)
Blue light has a wavelength of ___________.
450nm
What is blue lights frequency in water based on a wavelength of 450nm? Would the frequency be different in a vacuum?
5x10^14 hz No! Frequency never changes!
What is blue lights frequency in a vacuume based on a wavelength of 450nm?
6.67x10^14 hz Hz= 1/sec or sec^-1
Red light has a wavelength of _______ .
700nm
A higher frequency has __________, __________ wavelengths in a period than a lower frequency.
A higher frequency has MORE, SHORTER wavelengths in a period than a lower frequency.
What are the approximate frequencies for Red Orange Yellow Green Blue Violet
ALL x 10^14 Hz Red: below 4.82 Orange: 5 ish Yellow: 5-5.2 Green: 5.2-6 Blue: 6.1-6.5 Violet: above 6.59 At least remember: Orange 5 Green 6 Violet 7
The portion of the electromagnetic spectrum that is absorbed by the photoreceptors in our eyes are what?
About 400-700nm. The visible light spectrum.
Amplitude is defined as what?
Amplitutde: The maximum displacement of the vibrations of the wave. (Basically the distance between the peak of the wave and the middle of the wave.
Geometric Optics describes _______ __________________ in terms of rays. For our purposes light travels from _________ to __________.
Geometric Optics describes LIGHT PROPAGATION in terms of rays. For our purposes light travels from _LEFT to RIGHT_.
Frequency is measured in ________________. Visible light spectrum frequency is approximately between ________ and __________.
Hertz (hz) Visible frequency is approximately 4 - 7.5 x 10^14 hz
How is energy related to frequency and wavelength?
Higher energy = Higher Frequency = shorter wavelength
Light perception depends not only on the wavelength of the light but also on what?
Psychophysiological response
What are the approximate wavelengths for Red Orange Yellow Green Blue Violet
Remember: nm = 1x10^-9m Red: 700nm Orange 600nm Green 500nm Blue is 450nm Violet 400nm
Light is only 1 particular type of energy (true or false)
TRUE!
True or false. Frequency is CONSTANT for a particular light, so it does NOT change when entering a new medium.
TRUE!
Define a cycle.
The completion of a regular periodic event.
Wavelength is defined as what?
The distance between two consecutive peaks or troughs of a wave.
What is a Period? And what is the unit?
The inverse of frequency. T = 1/f Unit is seconds
Define frequency
The number of cycles of a wave that pass a reference position in a certain amount of time. We use hertz to define that amount of time (Cycles per second).
Does a longer wavelength have a higher or lower amplitude than a shorter wavelength?
These two are unrelated!
Light waves (and water waves) both are what type of waves?
Transverse waves! These oscillate perpendicular to the direction of light travel.
Name the common types of electromagnetic waves along the electromagnetic spectrum in terms of low to high frequency hint: remember pneumonic
V=wavelength(F) (Long waves) Radiowaves Microwaves Infrared Visible (RED-BLUE) Ultraviolet X-Ray Gamma
What is the unit for Amplitude?
m or cm
How long is an approximate radio wavelength? Compare this to how long a visible wavelength is.
radio: 1 meter. Visible 400-700nm!
A hz is equal to what?
sec^-1