Solar Tea Kettle: an Experiment

By Victoria Chu

Purpose

The purpose of this experiment was to find out whether a bottle covered in black paint would absorb more heat than one that is clear.

Materials

• Two identical glass bottles• Four tea bags• Cold water• Black paint• Thermometer

Procedure

1. First, one bottle was painted black while the other was left clear.

2. Next, both bottles were filled with the same amount of cold water.

3. Then two tea bags were put into each bottle.

4. The temperature of the water in both bottles were taken and recorded. This was done every two hours, for six hours.

Observations

When I first started the experiment,the temperature of the water was low. Under the sun, the temperature started rising. The colour of the water also changed soon after the bottles were put in the sun because of the teabags. The temperature was highest in the fourth hour. When it became cloudy in the fifth hour, the temperature went down again.

Temperature of water at 12:00pm (when the experiment started):

The Black bottle: 23°C

The Clear bottle: 23°C

Temperature at 2:00pm

The Black bottle:39.8°C

The Clear bottle: 36.3°C

Temperature at 4:00pm

The Black bottle:43.2°C

The Clear bottle:41.4°C

Temperature of water at 6:00pm (when it became cloudy, at the end of the experiment)

The Black bottle:35.2°C

The Clear bottle: 34.1°C

Conclusions

After this experiment I learned that darker colours can absorb heat betterthan lighter colours. The temperature of the water in the black bottle heat up soon after it was put under the sun, and throughout the whole experiment it was hotter than the water in the clear bottle.

Big idea

Darker colors absorb heat better than light colours because the light colours reflect the light that shines on it, butthe dark colours absorb light and convert it into heat. So when an object such as a bottle is covered in a dark colour, it will heat up faster than one without the dark colour.

Thank you all for listening!

Do you have any questions?