elliemae2891

When you mixed room temperature salt and room temperature water, the mixture changed temperature. If you were to leave this mixture undisturbed for several hours, what would happen to the temperature? Please explain.

The center of the earth is pretty hot, and as you dig downwards the temperature goes up by about 25 C per kilometer. This becomes a problem in deep mines. Ten kilometers down the temperature is 250 C warmer (450 F warmer) than the surface -- definitely toasty warm! This temperature difference causes energy to move to the surface by thermal conduction. How could I use some value for the thermal conductivity of rock, calculate how much energy per time is conducted through 1 square meter (in Watts). To put this number in context, how could I compare it to the rate that energy arrives from the sun (about 1000 Watts for a square meter, when the sun is directly overhead).

If you fill a cup with ice, about half the volume is ice and half is air. Assuming this, how can you estimate how long it will take to melt the ice in your microwave set on "high."

Electricity costs about $0.10 per kilowatt-hour (which means, 1000 W for 1 hour: 3,600,000 Joules!). How much does it cost to make a tankful of hot water?

An electrical water heater can deliver 4500 Watts (which means, 4500 Joules per second).

A 40 gallon water heater contains 160 Kg of water. The water coming from the water company is at 10 C (50 F; when it comes out of the water tank, its temperature is 60 C (140 F). How much energy does the water heater add?

I have been riding 4-wheelers for quite a while, but never had to use a clutch. Most of mine have been the manual shift honda without a clutch. I am wanting to get a sport quad but I am worried about stalling it with the clutch. How hard is it to learn the clutch?

When we place objects of different temperatures in a room, they usually come to the same temperature. How does the second law of thermodynamics affect this?

The temperature of deserts varies very strongly from day to night; it varies somewhat in inland places; it varies very little near large bodies of water. What role is played by changes of phase in this difference?

The temperature of deserts varies very strongly from day to night; it varies somewhat in inland places; it varies very little near large bodies of water. I understand that all of the aspects of transport and storage of energy play a role in creating this difference. How does convection play into this effect?

The temperature of deserts varies very strongly from day to night; it varies somewhat in inland places; it varies very little near large bodies of water. All of the aspects of transport and storage of energy play a role in creating this difference. How does conduction play into this effect?

When there is a late cold snap, fruit farmers spray water on their trees to prevent the flower buds from freezing. The water comes out of the farm pond and is not at all warm! How does spraying the cold water on the trees prevent freezing damage?

When we place objects of different temperatures in a room, they usually come to the same temperature. But a damp object, even if it starts at room temperature, becomes cooler than the room. How does this play into the second law of thermodynamics?

Please be clear about what the original form was, how it was converted, and whether the resulting thermal energy would be easy to detect with a thermometer.

You can bake potatoes in a conventional oven, or in a microwave oven. Baking potatoes in the oven takes "40 minutes to an hour, depending on their size" in a 425o F oven, while in a microwave, the length of time to cook depends on how many potatoes you are trying to cook: 4 minutes for one, 8 minutes for 2, ... , a half-hour for 8. The two ways to cook a potato differ in many ways: please discuss how these differences give rise to the different instructions for the use of an oven and a microwave oven.

What are four examples from around the house where we choose things because they are good thermal conductors?

If you cover your home thermostat with a blanket, will it make the house hotter or colder, or have some other effect?

The wind certainly makes you feel cold. Yet a fan blowing on a thermometer does not change the reading! Even though both thermometers and people have red noses, they differ in the effect that the wind has. How could you discuss the other respects in which you differ from a thermometer that that might explain this?