science presentation

SCIENCE PRESENTATIONWHICH CUP KEEPS COFFEE

THE HOTTEST?By Natasha Wood

15101189Tuesday 10-1

Aim

This experiment has been done to determine which coffee cup keeps the temperature of the liquid most stable.

Hypothesis

I hypothethise that the stainless steel mug will keep the Liquid the hottest and that the paper cup will lose heat the quickest. This is due to the fact that stainless steel is a better conductor of heat.

Variables

Independent Variable: Coffee Cups Dependent Variables: Temperature of the

liquid. Controlled Variables: Time, outside

temperature, amount of liquid used, starting temperature, using the same coffee cups for repeat trials, thermometers & type of liquid.

Materials

Coffee cups Measuring cup Thermometers Paper &pen Hot Water Kettle

Method

1) Set up cups, thermometers, kettle and recorded outside temperature.

2) Boiled the Kettle. 3) Measure water temperature. 4) Measure out ½ cup of water and distribute

to each cup. 5) Put thermometer in cup and screw on the

lid. 6) Measure temperature every 5 minutes. 7) Repeat steps 1-6, 2 times. 8) Average and graph results.

Table of results

Plastic Paper Metal

1 2 3 Avg 1 2 3 Avg 1 2 3 Avg

Start 86⁰C 86⁰C 86⁰C 86 86⁰C 86⁰C 86⁰C 86 86⁰C 86⁰C 86⁰C 86

5mins

69 72 74 69 65 70 72 71 70 76 78 74

10min

64 65 70 64 62 62 68 66 65 68 74 69

15min

60 61 65 58 55 56 63 61 61 64 70 65

20min

55 58 60 55 52 54 60 57 57 61 66 61

25min

53 54 56 51 48 49 57 54 54 56 62 57

30min

50 52 54 48 45 47 54 52 51 54 58 54

Results

The paper cup was the worst performer, resulting in a temperature drop of 1.26 C per minute over the 30 minute period.

The temperature of the liquid within the plastic cup dropped at a rate of 1.13 C per minute.

The metal cup gave the best results with a drop of only 1.06 C per minute.

FigureTemperature changes over time using different insulators.

Discussion of results

The paper cup was the worst performer because paper is a poorer insulator when compared to plastic and metal (Dawson & Venville, 2007).

Metal is a more efficient due to the fact that the vacuum seal traps the heat within the cup and metal is a greater heat conductor than plastic (Kutz, 1968).

References

Dawson, V., &Venville, G.(Eds.). (2007). The

art of teaching primary

science. Crows Nest, NSW: Allen & Unwin.

Kutz, M. (1968). Temperature Control.

Sydney, NSW: John Wiley &Sons, Inc.