To
solve this problem, we assume that the wavelength of the light in air is 500
nanometers.
For this case we
only need the refractive index of the polystyrene. For an antireflective
coating, we need a quarter of wave thickness at the wavelength in the air. Which
means that the antireflective coating needs to be as thick as 1/4 of the
wavelength, divided by the coating’s refractive index. This is expressed
mathematically in the form:
x = λ / (4 * n)
where,
x = thickness
λ = wavelength
of light
n = index of
refraction of polystyrene
Substituting:
x = 500 nm / (4
* 1.49)
x = 500 nm / 5.96
x = 83.90 nm
F - False.
The nucleus of an atom is positively charge.
<span>The magnitude of her acceleration as she travels this 12 meters is 1.875m/s^2</span>
To solve this problem it is necessary to apply the concepts related to energy in photons. Although these although they have no mass have energy and are defined as
Where,
c = Speed of light
h = Planck's constant
= wavelength
f= Frequency of the radiation
In addition to this we know that the maximum kinetic energy in a photon is given by the formula
Where,
Amount of energy binding the electron to the metal
can be expressed also as
Replacing the terms then we have to
Re-arrange to find
Replacing with our values,
Therefore the maximum kinetic energy is 2.49eV
<em>Note: Speed of light is converted to nanometers. </em>