A simple compass can be made by placing a small bar magnet on a cork floating in water. Required:
a. What fraction of a plain cork will be submerged when floating in water?
b. If the cork has a mass of 11.5 g and a 22.5-g magnet, made of iron with a density 7.80 g/cm^3, is placed on it, what fraction of the cork will be submerged?
c. Will the bar magnet and cork float in ethyl alcohol?

Beryl states that insulation with the smallest possible thermal conductivity is best to keep a house warm in winter, but worst for keeping a house cool in summer. sapphire insists the reverse is true: low thermal conductivity is good in the summer, but bad in the winter. which one, if either is correct? a. beryl, because low thermal conductivity results in low heat transfer. b. beryl, because low thermal conductivity results in high heat transfer. d. sapphire, because low thermal conductivity results in high heat transfer. e. neither, because low heat transfer is desirable both in summer and in winter.