when you are in a bathtub filled with hot water and you stay still for a while the water seems to be cooling but as soon as you move it slightly you would feel the heat coming back? is it because your body absorbs the heat from the water in that specific area? (if the body can do such thing, that is!) or is it something else?

If so does this depend upon factors such as length and texture of hair, amount of straightening, and temperature of straighteners (average 210 - 220C)?

My girlfriend and I were having an argument the other day. Sometimes when it is cold in the kitchen, I turn in the gas hob to warm the place up. The argument is that she claims that the room gets hotter if you put a pot of water on the hob to boil and let the room get steamy. I disagree and think that the room gets just as hot without boiling a pot of water.

Who is right? Does the room get hotter with the pot of water or does the room get just as hot without it?

The cellar in question is three floors below the loft.

David Clarke, Manchester, UK

In common parlance, one would say the body 'burns' food, and, indeed, we are warm creatures due to some kind of exothermic reaction(s) inside us, yet our muscles and brain work on electrical impulse. Is this the most efficient conversion of heat to useful energy we know of, or is the electrical energy converted from chemical potential energy somewhere?

Surely if they are good conductors then they will absorb the heat easily, just as they do when you place your hand onto the surface?

We have a toaster with a plastic lid. One is supposed to put the lid on only after the toaster has cooled off, to protect the inside of the toaster from dust. But apparently some time ago someone neglected the pictogram and put the lid on while the toaster was still rather hot. Now in the most heat-exposed places, the plastic has become of a clearer transparent color, more irregular shape of surface, and there are a lot of fine bubbles inside, about half a millimeter in diameter. My question is: What is in the bubbles and how did it get there? Did the plastic contain fine dispersed air initially? Or maybe water or some organic components that "boil" at a moderate temperature?

While visiting Magna in Rotherham recently, my son asked me a question I couldn't answer. What is the bucket that pours the molten steel made of? And how is it made? It must be made of an alloy with a higher melting point than steel, so how is it made? And how is the machinery used to make that made? And how is the machinery used to make that machinery made? You could go on for some time with this chain of production, but it all comes down to how do you make machinery for something that has a massively high melting point? What is it made of and how is it made?

Thanks for your help,

Peter and Alfie Finan, Haworth, West Yorkshire

Imagine you heated a room to more than the temperature of a fire and then lit a fire in that room, would the fire heat up the room further or cool it down? I thought of this question when i noticed that you blow on hot food to cool it, and blowing on ice cream melts it.