What type of fingerprints is invisible to the naked eye?

Light traveling in a medium with a refractive index 1.19 is incident on a plate of another medium with index of refraction 1.79. at what angle of incidence is the reflected light fully polarized?

The diagram shows a series of volcanic island and a hot spot determine the direction of movement of the tectonic plate that for the island

You charge a parallel-plate capacitor, remove it from the battery, and prevent the wires connected to the plates from touching each other. when you increase the plate separation, what happens to the following quantities?