Why do you think glass bottles keep water cold longer?

Because glass is not a good heat conductor. What it means is that heat isn't transfered through its structure as quickly as it would with metal, for instance. Because heat can't penetrate glass as quickly, the contents stay at the same temperature for longer.

low freq = 100 mhz

low wavelength =101.7m

length = 3x10^8/freq

since you're a real machine, your ama is always less than your ima, because you can never totally eliminate friction.