Τετράδιο Εργασιών, σελ. 52 - 53
Why was Asterix forced to give up the spear, while Obelix still holds it?
Τετράδιο Εργασιών, σελ. 52 - 53
As I heat the tip of the needle, the drops of wax melt and fall. The one closest to the flame falls first and the one closest to my hand last.
Τετράδιο Εργασιών, σελ. 52 - 53
Heat is transferred by conduction from one end of the needle to the other.
I used cork so that the heat wouldn't transfer to my hand and burn me.
Τετράδιο Εργασιών, σελ. 52 - 53
Can you explain why Asterix was forced to give up the spear, while Obelix still holds it?
The heat flows from the hot end of the spear to the cold end. Thus it reaches first Asterix's hands and then Obelix's.
Τετράδιο Εργασιών, σελ. 52 - 53
If you touch a pot on the stove, you will burn. But if you grab it by the handles, you won't. Can you explain why we don't get burned when we grab the pot by the handles?
The pot is made of steel, which is a good conductor of heat. The handles are made of synthetic material, which is a poor conductor of heat. That's why we can safely grab it by the handles.
Τετράδιο Εργασιών, σελ. 52 - 53
The mother should have said "wear thick woolen clothes that are bad conductors of heat".
A mother tells her child in winter: “Put on warm clothes so you don’t catch a cold.” However, if we were to measure with a thermometer, we would find that the clothes and the room are the same temperature. What should the mother have said more correctly?
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