What is the amount of thermal energy needed to make 5 kg of ice at - 10 °C to steam at 100 °C? (Heat of fusion of Ice is 3.34 x 10 j/kg, specific heat capacity of
ice is 2.09 x 10 3 J/kg °C, Specific heat capacity of water is 4.186 x 10 ? J/kg° C,
Heat of vaporization of water 2.26 x 10 J/kg)

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