APES heat homework part one

APES heat homework part one

You are given three containers:

• A: Open metal container
• B: White styrofoam container, with a lid
• C: Closed thermos with vacuum between layers

1. Explain the heat transfer modes you would expect from each of these containers
2. How would you improve the heat decay constant (k) for each container?
3. Given the data below, calculate the value for k for each container:

• Starting temperature: 75°C
• Room temperature: 20°C
• Time: 1200 seconds

1. Use the three heat modes to explain wind and weather
2. Using the three heat modes, explain how each is connected to global warming
3. Explain the positive feedback loop for global warming, and how we have impacted it
4. Why is using k a better way for detectives at a murder scene to determine time of death than just temp?
5. Explain how you could be a future millionaire by changing how we store hot water
6. What is the difference between storing energy as hot water and storing it in a battery?
7. Why are some cities banning the use of gas water heaters?
8. Your hot water heater heats water to 50°C from 20°C which takes 1 hour. If this takes place twice each day, and costs you $1.50 each time, how much money are you spending each month to heat hot water? (month is 30 days)
9. If you could invent something that would improve the heat decay (k) of this hot water heater by 10%, how much would you save each month? Each year?
10. There are about 330 million people in the US. Each home is about 3 people. If every home has a hot water heater, how much money will you be saving each year total?
11. If each household pays $180 for your invention, how many months would it take to pay this off from the savings?
12. If the device lasts about 20 years (240 months), how much money did it save each household?
13. Multiply this by the number of homes in the US (above). How much did you save total?