1. What is R of a fiberglass batt that is 6 inches thick? Give two answers,...

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1. What is R of a fiberglass batt that is 6 inches thick? Give two answers, one in American units based on BTUs, one in SI units based on joules. 2. You surely know the tale of the 3 little pigs and the big bad wolf. Which of the three little piggies picked the best insulator for their building and why? The one who built with straw, wood or brick? 3. On cold day the air outside temperature is 0 degrees Celsius and the ground under the house is 10 Celsius. The optimal inside temperature for little pig habitation is 20 Celsius. Pig Number 2 has built his house of 1-cm thick wood planks and the building is a 5x5x2 meter box, including the floor. What is the heat current out of this house in watts? 4. What would be the heat flow if the all the walls, ceiling and floor were insulated with 15 cm of fiberglass in addition to the wood? This would also be the power requirement for a heating system that would keep the home comfortable at 20 Celsius when it is 0 Celsius outside. 5. How would the addition of 2 south-facing windows that accept sunlight affect the heating requirements on a sunny day. Consider a simple example where both windows are 1-meter on a side, are made of thermally insulating glass which has an air-gap so that it does not readily conduct heat, and the Sun delivers 1 kW of energy per square meter directly through the window. 1. What is R of a fiberglass batt that is 6 inches thick? Give two answers, one in American units based on BTUs, one in SI units based on joules. 2. You surely know the tale of the 3 little pigs and the big bad wolf. Which of the three little piggies picked the best insulator for their building and why? The one who built with straw, wood or brick? 3. On cold day the air outside temperature is 0 degrees Celsius and the ground under the house is 10 Celsius. The optimal inside temperature for little pig habitation is 20 Celsius. Pig Number 2 has built his house of 1-cm thick wood planks and the building is a 5x5x2 meter box, including the floor. What is the heat current out of this house in watts? 4. What would be the heat flow if the all the walls, ceiling and floor were insulated with 15 cm of fiberglass in addition to the wood? This would also be the power requirement for a heating system that would keep the home comfortable at 20 Celsius when it is 0 Celsius outside. 5. How would the addition of 2 south-facing windows that accept sunlight affect the heating requirements on a sunny day. Consider a simple example where both windows are 1-meter on a side, are made of thermally insulating glass which has an air-gap so that it does not readily conduct heat, and the Sun delivers 1 kW of energy per square meter directly through the window.

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1 The Rvalue of a material is a measure of its thermal resistance It indicates how well a material c... View the full answer