Investigate why if you are caught in a heavy snow storm,you should rather not eat ice for hydration,but rather melt it to approximately your body temperature

The main reason for melting the snow first is that snow is colder, meaning it can cause frostbite to skin and increase the chances of hypothermia. Moreover, snow is less dense than water, so you will have to eat a lot of snow to obtain a considerable amount of water, which will be difficult. 

A similar principle is observed with light as it is with sound. If an object is moving away from you the wavelengths gets longer, and towards the red light spectrum of the visible light spectrum, whereas if an object is moving towards you the wavelength will decrease towards the blue end of the spectrum