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www.GOALias.blogspot.comWhat you have learnt• Our sense of touch is not always a reliable guide to the degree of hotnessof an object.• Temperature is a measure of the degree of hotness of an object.• Thermometer is a device used for measuring temperatures.• Clinical thermometer is used to measure our body temperature. Therange of this thermometer is from 35°C to 42°C. For other purposes, weuse the laboratory thermometers. The range of these thermometers isusually from –10°C to 110°C.• The normal temperature of the human body is 37°C.• The heat flows from a body at a higher temperature to a body at a lowertemperature. There are three ways in which heat can flow from oneobject to another. These are conduction, convection and radiation.• In solids, generally, the heat is transferred by conduction. In liquidsand gases the heat is transferred by convection. No medium is requiredfor transfer of heat by radiation.• The materials which allow heat to pass through them easily areconductors of heat.• The materials which do not allow heat to pass through them easily arecalled insulators.• Dark-coloured objects absorb radiation better than the light-colouredobjects. That is the reason we feel more comfortable in light-colouredclothes in the summer.• Woollen clothes keep us warm during winter. It is so because wool is apoor conductor of heat and it has air trapped in between the fibres.Exercises1. State similarities and differences between the laboratory thermometerand the clinical thermometer.2. Give two examples each of conductors and insulators of heat.3. Fill in the blanks :(a) The hotness of an object is determined by its __________.(b) Temperature of boiling water cannot be measured by a_____________ thermometer.(c) Temperature is measured in degree ______________.HEAT4545