A ray of light goes through a piece of plastic at a speed of 100,000,000 m/s. What is the index of refraction for the plastic? (nearest whole number)

An unknown substance has a melting point of 1064 ∘c, is insoluble in water, conducts electricity as a solid, and is hard. given these properties, which of the following are possible identities for the unknown substance? check all that apply. view available hint(s) check all that apply. sio2 f2 au kbr

Henry, whose mass is 95 kg, stands on a bathroom scale in an elevator. the scale reads 830 n for the first 2.4 s after the elevator starts moving, then 930 n for the next 2.4 s. part a what is the elevator's speed 4.8 s after starting? express your answer with the appropriate units.

In a hydrogen molecule there are a total of four charges, 2 protons in the two nuclei, and 2 electrons. how many unique charge-pairs are there (without double counting)?