1. Temperature Control and Ventilation

2. Conduction - The transfer of heat through a solid. - Particles that make up a substance are vibrating all the time - As heat is applied vibrations become more vigorous, therefore increasing Kinetic (movement) Energy.

3. In a solid particles are held closely together. If one end of the solid is heated, particles at that end gain energy and vibrate more. These particles then bump into neighbouring particles and transfer energy causing these particles to then vibrate and so on.

7. Heat energy is transferred from one place to another by the movement of gas or liquid particles. When one part of a liquid is heated, particles vibrate more and push each other apart. So part of the liquid expands and becomes less dense (lighter) making it rise upwards and it is replaced by cooler liquids which is then heated and raises.

9. These are set up in everyday objects, examples: - Hot water tanks. ( students explain) - In a refrigerator, air at the top cabinet is chilled so that it becomes more dense and sinks. Warmer air raises to the top and is chilled and then sinks and so a cooling convection current is set up and the temperature of the air in the frig decreases. - Sea Breeze, this is an example of natural convention currents.

10. During the day land heats up more quickly than the sea. Land heats the air above it which raises and is replaced by colder air from over the sea. This convection current can be felt as an onshore breeze blowing from sea onto land.

11. At night land cools rapidly, but the temperature of the sea changes very little. Land becomes cooler than the sea so the air over the sea becomes heated and colder air moves from over the land to over the sea. The change in direction produces offshore breeze at night blowing from the land onto the sea.

13. Radiation is the transfer of heat energy by electromagnetic waves. Unlike conduction and convection, radiation does not require fluids, so it is the only way in which heat can be transferred through a vacuum.

15. A thermostat is used to keep something at a particular temperature. A bimetallic strip is made from two strips of different metals (iron and brass) riveted together. Both of the metal expand when they are heated, but by different amounts. If the metal is heated the brass expands more than the iron and the metal forms a curve. The bimetallic strip can be used as a thermostat to keep an electrical iron at the correct temperature.

17. Students are asked to research and explain the principle by which thermostatically controlled household appliances operate. As in appliances such as electrical and gas ovens and electrical irons

18. Temperature is the measure of the amount of heat energy or the hotness of an object. Temperature is measured using a thermometer. Liquid-in-glass thermometers - Uses the expansion of a liquid to measure the change in temperature. - A glass bulb filled with a liquid (mercury or alcohol) is attached with a capillary tube. - The expansion take place because the particles of the liquid gain kinetic energy pushing each other further apart.

20. This thermometer is used to measure the temperature of the human body.

21. These are used to measure the maximum and minimum temperatures over a period of time. The thermometer contains both mercury and alcohol in a U-shaped tube.

23. These do not use the expansion of mercury to measure the temperature it uses thermal radiation.

24. Body temperature Human beings are endotherms and are able to maintain a constant body temperature that is independent of the external environmental temperature. To maintain a constant body temperature heat loss must be equal to heat gain.

25. Heat can be gained by the body from: - Cell respiration - Direct radiation from the sun and fires or radiators - Radiation reflected from other surfaces - Conduction from warm surfaces of from consuming hot food or drink - Convection from the surrounding

26. Heat maybe lost from the body by: - Direct radiation when the body is hotter than the environment - Conduction to cooler surfaces - Convection to the surrounding - Evaporation of water in sweat

27. Effects of heat - Sunburn is a condition caused by direct exposure to radiation from the sun. The skin becomes red, blisters occur and eventually the top layers of the skin is peeled off. - Skin cancer caused from the exposure to the sun. - Heat exhaustion caused from too much exposure to the sun. - Heat stroke is a severe condition which occurs when the temperature regulation mechanism breaks down. The sweating mechanism fails.

28. Relative Humidity - It is the measure of the quantity of water vapour in the air. - Warm air can hold more water vapour than cold air because warm air is less dense. - When the air temperature increases the relative humidity decreases. - Relative humidity has an effect on the ability of to loose heat by sweating.

29. Students answer - What occurs in a dry/hot climate - What occurs in a wet/cold climate

30. The composition of air around us can be changed by: - Breathing - Chemical pollutants - Pollen - Dust - Bacteria - Tobacco smoke - Odours These changes may make us feel hot, sticky, dizzy, give us headaches, and make s less efficient at work. Some pollutants may cause illness such as fever, asthma, even cancer.

31. Ventilation maybe simply be: - Opening a window - Use of small vents to replace stale air Air conditioning- maybe used to prevent the inside of a building becoming uncomfortably hot. A fan is used to move hot air over a set of cooling coils, the coils contain a fluid called a refrigerant. Students research the working mechanism of an air conditioning unit.

32. Humidifiers These are devises used to increase or maintain the humidity of the air.