Τετράδιο Εργασιών, σελ. 54 - 56
Observe the diagram below of the central heating system of a house. By burning oil, energy is transferred to the water that passes through the pipes in the boiler. The hot water reaches the radiators located in the various rooms of the house.
Radiators transmit heat to the air around them. The warm air carries the heat into the room.
But you know that water and air are poor conductors of heat.
So how is heat transferred?
Τετράδιο Εργασιών, σελ. 54 - 56
The hot water balloon floats in the bucket.
The balloon with the cold water sinks into the bucket.
Τετράδιο Εργασιών, σελ. 54 - 56
We observe that the colored water rises from the glass into the mug.
Τετράδιο Εργασιών, σελ. 54 - 56
The edge of the paper moves upwards. The hot air, like the hot water in the previous experiments, rises upwards.
Τετράδιο Εργασιών, σελ. 54 - 56
In liquids and gases, heat is also transferred by currents. The liquid or air that has a higher temperature moves upward, transferring heat.
Τετράδιο Εργασιών, σελ. 54 - 56
The burning of oil heats the water in the boiler. The hot water reaches the rooms with the help of the circulator, transferring the heat to the bodies through currents. The air near them heats up and rises, carrying the heat into the room with currents.
Can you briefly describe the operation of the central heating system?
Τετράδιο Εργασιών, σελ. 54 - 56
From the stovetop to the pot, heat is transmitted by conduction. The potatoes are heated in the water, the heat is transferred to them by currents.
How is energy transmitted from the stove to the pot and how is it transferred to the potatoes?
Τετράδιο Εργασιών, σελ. 54 - 56
As the warm air rises, it carries with it small pieces of debris and dust, which stick to the wall above the radiators and get it dirty.
There are various pieces of trash in the air that are so small that we can't see them. Can you explain why the wall above the radiators turns black?
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