Question

your feet are cold when you go to bed and you want something to warm them up. Would you prefer to have a bottle filled with hot water or one filled with an equal mass of aluminium block at the same temperature as the water? explain.

Answer 1

Well, the block of aluminum would transfer the heat much faster than water, due to its lower specific heat. If the temperature is really hot, I would prefer the water, so that my feet don't get burned, but if the block is only warm and I want my feet warmed up quickly, I would choose the aluminum block.

Answer 2

Don't confuse specific heat capacity with thermal conductivity. The issue is how much thermal energy is stored in each substance. Because water has a much higher specific heat capacity than does aluminum, the water would have much more thermal energy stored in it, and would therefore provide warmth for a longer period of time.