All AP Physics 2 Resources
Example Questions
Example Question #101 : Optics
Malus' law:
Where is the intensity of polarized light that has passed through the polarizer, is the intensity of polarized light before the polarizer, and is the angle between the polarized light and the polarizer.
Unpolarized light passes through a polarizer. It then passes through another polarizer at angle to the first, and then another at angle to the second. What percentage of the original intensity was the light coming out of the second polarizer?
None of these
Use Malus' law.
The light's intensity is reduced by the final two polarizers. We will need to use Malus' law twice.
Where is the initial intensity after the first polarizer.
is the intensity after the second polarizer.
is the intensity after the third polarizer.
is the angle between the first and second polarizers.
is the angle between the second and third polarizers.
Combine equations:
Plug in values:
Example Question #2 : Other Optics Principles
Malus' law:
Where is the intensity of polarized light that has passed through the polarizer, is the intensity of polarized light before the polarizer, and is the angle between the polarized light and the polarizer.
Unpolarized light passes through a polarizer. It then passes through another polarizer at angle to the first, and then another at angle to the second. What percentage of the original intensity was the light coming out of the third polarizer?
None of these
Use Malus' law.
The light's intensity is reduced by the final two polarizers. We will need to use Malus law twice.
Where is the initial intensity after the first polarizer.
is the intensity after the second polarizer.
is the intensity after the third polarizer.
is the angle between the first and second polarizers.
is the angle between the second and third polarizers.
Combine equations:
Plug in values:
Example Question #3 : Other Optics Principles
You are passing a ray of light through clear alcohol to determine properties. You shine the light ray exactly to the surface of alcohol.
Suppose that the alcohol surface will completely reflect the incoming light beam like a mirror. At what angle will the angle of reflectance be to the normal of the surface of the alcohol?
Assuming the alcohol works like a perfect mirror, the angle of reflectance will equal the angle of incidence. Therefore, the angle of reflectance will be
Example Question #4 : Other Optics Principles
The diffraction of waves refers to the
slowing down of one wave in the presence of another
change in wavelength that occurs when two waves cross one another
resultant disturbance of two or more waves at every point
phase change of 180 degrees that occurs on reflection of a wave at a fixed end
spreading of waves from their initial line of travel
spreading of waves from their initial line of travel
Diffraction is the bending of light around an object. It is seen in the Double Slit experiment in which waves are spread out from their initial line of travel.