Energy Background Energy Forms and Transformations Integrated Science 4 Honors Name: Per:

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1 Energy Background Energy Forms and Transformations Integrated Science 4 Honors Name: Per: Humans use energy for a variety of purposes, some that are necessary and some that are not. To address the questions and issues associated with human energy use, we need a basic understanding of the concept. This includes the relationship between matter and energy. We explored this relationship in a natural system through our study of photosynthesis and agriculture. In this part of the course, we will pay more attention to human-built systems and their use of matter and energy. As an important aspect of our energy work will be to measure/quantify energy use. All forms of energy can be measured and all are measured using different units. Energy can be transformed from one type to another and many of our built systems rely on this principle in their function. Part of our measurement of energy includes calculations that allow us to convert between different energy types. We will practice these energy units and calculations in this examination of energy basics. After completing this background work, you should be able to explain in your own words the following questions: What are the Laws of Conservation of Matter and Conservation of Energy? What are the First and Second Laws of Thermodynamics? What are some different forms of energy? What are some specific examples of energy transformations? What is the relationship between matter and energy? Ø Energy Transformations- Qualitative Analysis 1. According to the First Law of Thermodynamics, energy cannot be created or destroyed, but can be converted, or transformed from one form into another. Energy transformations occur when we use energy. Consider the devices below. For each device, list the initial form of energy in the device and the converted form of energy. Device Initial Form of Energy Converted Form of Energy 2. Using your thinking from above, look at the devices pictured in Diagram 2. In each of the empty boxes below, write the number of the device (from Diagram 2.) that could convert energy from the form listed on the left side to the form named at the top. Refer to the light bulb example that has been done for you. Place only one number in a box and no number is used more than once.

2 Diagram 1. Energy Transformation Chart A. 3. Choose any one specific energy transformation from the chart above. For that transformation: describe the transformation in terms of kinetic and potential energy describe any energy transformations that occur either before or after the transformation from the chart describe another specific example of the same energy transformation

3 Example: A. light bulb Diagram 2. Devices and Processes

4 Ø Energy Transformations- Quantitative Analysis 1. Use the following conversion factors to complete the problems below. You may work with a partner, but be sure that you know how to set-up and solve all of the problems. 2. For each problem, show your work. You must include the units with each step. Indicate your final answer, including the units, with a box. Pay attention to the number of decimal places you use in your final answer. Conversion Factors: Mass (1) kg = 2.2 lb (1) ton = 2000 lb (1) metric ton (MT) = 1000 kg Energy Conversions UNIT Btu ft-lb joule calorie kwhr 1 Btu = x ft-lb = 1.29 x x joule = 9.48 x x calorie = 3.97 x x 10-1 kw-hr = x x x Fossil Fuel Conversions Crude Oil 1 barrel (bbl) = 42 gallons 1 barrel (bbl) = 0.13 MT 1 barrel (bbl) = 5,800,000 BTU 1 barrel (bbl) = 5.8 x 10 BTU Natural Gas 1 ft = 1031 BTU 3 1 therm = 100,000 BTU Gasoline 1 gallon = 125,000 BTU Coal 1 short ton = 25,000,000 BTU anthracite = 25.4 x 10 BTU/ton bituminous=2.2 x 10 BTU/ton lignite = 13.4 x 10 BTU/ton Electricity 1 kw-hr = 0.88 lb coal 1 kw-hr = 0.07 gal oil 1 kw-hr = 10.4 ft natural gas 3 Calculations: 1. How many pounds are there in 25 kilograms? 2. How many calories of heat are needed to raise 4300 grams of water 20 C to 80 C if a calorie is the amount of energy needed to heat 1 gram of water 1 C? 3. If the heating in the question above is done electronically, how many watt-hours of energy should you be billed for if 1 watt-hour = 80 calories?

5 4. A small solar panel raised the temperature of 4.4 pounds of water 20 F. How many BTU of heat were absorbed by the water? Number of Btu = (temp change of in F) x (number of pounds of water) 5. A car consumed 210 gallons of gasoline in two months. How many barrels of gasoline is this?. A large tank holds 750 pounds of water. The temperature of the water was originally 75 F. Due to cool weather, the temperature of the water dropped to 8 F. How many Btu of heat did the water lose? 7. How much energy, in Btu, is released when six barrels of oil are burned? 8. How much work (foot-pounds) does an electric motor accomplish that averages 250 kw-hr? 9. How many kw-hr are required for an electric heater to produce 1000 BTU? 10. How far will an automobile weighing 3175 lbs travel on 17 gallons of biodiesel that averages 30,133,4 calories/gallon?