How to find the angle of incidence.

Diffraction-Rayleigh criterion - Late one night on a highway, a car speeds by you and fades into the distance. Under these conditions the pupils of your eyes (average refractive index = 1.36) have diameters of about 7.0 mm. The taillights of this car are separated by a distance of 1.4 m and emit red light (wavelength = 660 nm in vacuum). How far away from you is this car when its taillights appea...

answer in nm - A proton is located at a distance of 0.410 m from a point charge of +8.30 µC. The repulsive electric force moves the proton until it is at a distance of 1.56 m from the charge. Suppose that the electric potential energy lost by the system is carried off by a photon that is emitted during the process. What is its wavelength?

Refraction problem - Light is reflected from a glass coffee table. When the angle of incidence is 56.0°, the reflected light is completely polarized parallel to the surface of the glass. What is the index of refraction of the glass?

Grating - When a grating is used with light that has a wavelength of 621 nm, a third-order maximum is formed at an angle of 18.0°. How many lines per centimeter does this grating have? answer in lines/cm

answer in joules and eV - The K characteristic X-ray line for tungsten has a wavelength of 1.84 10-11 m. What is the difference in energy between the two energy levels that give rise to this line? Express in joules and eV