P5: Optics Flashcards
Diffraction
1
Q
What happens when white light is diffracted?
A
A colour spectra forms, no clear fringes
2
Q
What is needed to observe a clear diffraction pattern?
A
- monochromatic light
- coherent source
- a narrow slit (same size as wavelength of light)
lasers are often used for this purpose
3
Q
What should we see when light is shone through a narrow slit?
A
A central bright fringe (maxima) with alternating dark and bright fringes on either side, which are caused by destructive and constructive interference.
4
Q
What is meant by intensity of light?
A
The number of photons per second
Power per unit area
5
Q
What are the 3 types of spectra?
in terms of light
A
- continuous
- line emission
- line absorption
