What factor is essential to the effectiveness of Joule's paddle wheel demonstration?

How many times did thomas edison mess up the light bulb

What is the thinnest soap film (excluding the case of zero thickness) that appears black when illuminated with light with a wavelength of 480 ? the index of refraction of the film is 1.34, and there is air on both sides of the film. express your answer in nanometers. hint 1. how to approach th

What is the orbital period of a spacecraft in a low orbit near the surface of mars? the radius of mars is 3.4×106m.