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# Heating Earth’s Surface

Title: Heating Earth’s Surface

Background Information:Offshore wind and on shore wind is always abig thing in sailing and fishing. They are caused by different of temperatureon land and in the ocean. It force people to think why there are different intemperature, and how big is the different.

There is much thing effect how fast something heat, like Thermal conductivity

Which means how fast do heat transferin this material. If we control the other entire thing that could affect howfast it heat, we could compare Thermal conductivity between materials.

Research Question: How do the heating and cooling rates ofsand andwater compare?

Hypothesis: If thereare same amount of sand and water, than sand heat faster and cool faster.

Materials: 2 thermometers ortemperatureprobes, 2 beakers, 250-mL, Sand, 200 mL, Water 200 mL, Lamp with 100-Wbulb, Metric ruler, Clock or stopwatch, String, Ring standand tworing clamps

Procedure: 1. Fill both beakers with 200 ml of sand andwater.

2. Put two thermometersinto both beakers fill with and water. Use string to hang the thermometer onthe water, same depth the thermometer in the sand does.

3. Put both bakers under alight from one 100-W bulb, 20 cm highthe breakers. Than wait 15 minutesto heat the water and sand, also 15 minute to cools down after turn off thelight. Measure the temperature every 3 minutes through the whole step.

4. Record the observation.

Data Collection:

 heating 3 min 6 min 9 min 12 min 15 min start water 25 o C 26 o C 28 o C 28 o C 28 o C 24o C sand 25 o C 26 o C 29 o C 30 o C 30 o C 24 o C

 cooling 3 min 6 min 9 min 12 min 15 min Start Water 26 25 24 24 24 28 Sand 30 28 26 26 25 30

Conclusion and Evaluation:

According to the data, sand wouldcool faster. It’s like different between a cup of water and a Thermal insulation kettle of water. If you heat both two containers from the outside .at the sametime, with the same volume of water inside the container. Water in the cup will heat fast but also coolfast. In the Thermal insulationkettle, water heat slow, but they also cool slowly. It’just likes water and sand. Sand is easier to heat, but also easy to lose itsheat. I think the different speed in heatingmight cause by different in grain size. But I can’t prove it.