2. What happens to the coloured water around the crystal when the heating begins?
When the water is heated it rises.
3. What happens to the coloured water near the surface of the water?
The coloured water near the surface begins to move in a circle in the Pyrex dish. It sinks in the part that is not being warmed by the burner..
Assignment 7:
(Groupwork)
When a see breeze is caused by convection, your group should be able to work out how a land breeze occurs. Make sketches and write your explanation here.
How does a land breeze occur?
During the night the land cools more quickly than the sea. The sea stays warm longer than the land. The warm air above the sea rises. Cooler air from the land blows towards the sea
Assignment 8:
1. What happens when you place the pane of glass in front of the heater?
Immediately you feel less heat.
(The heater / source of heat is not warm enough. Glass obstructs radiated heat from the heater, just like wood or cardboard)
Assignment 9:
1. Does your hand immediately feel the heat?
Yes
2. How does the heat reach your hand?
Through radiation.
3. Does the glass of the bulb prevent radiance?
No, because the radiation from a very warm (white hot) object can penetrate glass.
Explanation: Water conducts electricity and if you touch an electrical appliance while you are standing on the ground the current flows through your body to the ground. This can cause a fatal shock.
Leaner section
Content
Activity: to discover the properties of materials [lo 1.2, lo 2.1, lo 2.3]
4. MATERIALS CAN TRANSFER HEAT
If you hold a teaspoon in boiling water it feels warm when you touch it. Heat has thus been transferred from the water to the teaspoon. (This transfer of heat will not happen if both substances are the same temperature.)
Transfer of heat takes place in three ways: Conduction, convection and radiation.
4.1 Conduction:
This is the transfer of heat from one part of a substance to another, while each part remains in its place.
Conduction takes place in solids.
Most metals are good conductors of heat.
Non-metals such as glass, wood, rubber, paper, plastic and asbestos are poor conductors of heat.
Solids do not all conduct heat equally well.
Interesting uses of poor conductors:
Handles of pans, irons, etc. are made of wood or plastic or other poor conductors. This keeps ones hand from getting burnt.
Clothes (wool, cotton), the furs of animals, feathers, are all poor conductors of heat.
A glass table top and table mats of wood, cork, cotton or plastic protect shiny wooden table tops from being marked by warm pots.
Cold meat and cold drink can be kept cold on a long journey by wrapping them in newspaper or a woollen blanket. Paper and wool are poor conductors.
Ice can be kept for a long time in sawdust or wrapped in a towel.
Houses with thatched roofs are warm on cold days and cool on hot days.
House with flat roofs are insulated with a layer of glass fibre above the ceiling.
Eskimos build houses of snow to protect themselves from the cold.
Evolution models refer to mathematical and computational representations of the processes involved in biological evolution. These models aim to simulate and understand how species change over time through mechanisms such as natural selection, genetic drift, and mutation. Evolutionary models can be u
faruk
what are the modern trends in religious behaviours
shared standards of acceptable behavior by the group or appropriate behavior in a particular institution or those behaviors that are acceptable in a society
Lucius
that is how i understood it
Lucius
examples of societal norms
Diamond
Discuss the characteristics of the research located within positivist and the interpretivist paradigm
