Science

Method: Roughly equal quantities of hot water are poured into the beakers and the temperatures are read at 2 minute intervals for about a half hour. Fig 1 shows some of the boxes and beakers.

We have been investigating the different way in which heat can move from a hot body. It is appropriate, therefore, to look at how we might prevent or reduce the movement of heat.

Apparatus: Fibreglass, crumpled newspaper, carpet underfelt, some woollen socks, all used as insulation, plastic beakers, boxes in which the beakers are placed and surrounded by insulation, one beaker not placed in an insulated box, cardboard covers for the beakers with holes in the centre through which thermometers are inserted into hot water.

Results: Fig 2 shows graphs of the results. Series 1, the lowest curve, shows how the temperature changes in the water of the uninsulatd beaker. Series 2 is the beaker insulated with crumpled newspaper, series 3 uses the woolen socks, Series 5 the fibreglass and Series 6 the polystyrene.

Conclusions: The temperature of the water in the uninsulated beaker falls fairly quickly, but the other beakers cool much more slowly. Close examination of the results indicate that the temperature of the water insulated by the fibreglass drops slightly more slowly than the other insulations. It is difficult to draw more than indicative conclusions because the setup was rather crude. However, a general conclusion can be drawn that insulating a hot body can be quite efficient in preventing heat loss.

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