1. The light of incidents under the angle 60° from vacuum onto transparent medium. The anglr of refraction is 45°. what is the velocity of the light in this medium.
2. Dr broigle wave of electron in hydrogen atom is 0.5 10-10m. Calculate the velocity of electron.
3. The red helium-neon laser light incidents onto the surface of glass. What is the speed in the glass that has an index refraction of 1.50?