Homework Help is Here – Start Your Trial Now!
Engineering
Mechanical Engineering
A house has well-insulated walls 18.0 cm thick (assume conductivity of air) and area 450 m², a roof of wood 5.0 cm thick and area 270 m², and uncovered windows 0.75 cm thick and total area 34 m² ▼ Assuming that heat is lost only by conduction, calculate the rate at which heat must be supplied to this house to maintain its inside temperature at 22 °C if the outside temperature is -15 °C. Express your answer using two significant figures. conduction 1.6x105 W t Submit Part B = ✓ Correct Previous Answers If the house is initially at 10 °C, estimate how much heat must be supplied to raise the temperature to 22 °C within 20 min. Assume that only the air needs to be heated and that its volume is 750 m³. Take the specific heat of air to be 0.24 kcal/kg. C°. Express your answer using two significant figures. = 195] ΑΣΦ | 1 Qadded 40756942 → C Submit Previous Answers Request Answer X Incorrect; Try Again; 18 attempts remaining ? J

A house has well-insulated walls 18.0 cm thick (assume conductivity of air) and area 450 m², a roof of wood 5.0 cm thick and area 270 m², and uncovered windows 0.75 cm thick and total area 34 m² ▼ Assuming that heat is lost only by conduction, calculate the rate at which heat must be supplied to this house to maintain its inside temperature at 22 °C if the outside temperature is -15 °C. Express your answer using two significant figures. conduction 1.6x105 W t Submit Part B = ✓ Correct Previous Answers If the house is initially at 10 °C, estimate how much heat must be supplied to raise the temperature to 22 °C within 20 min. Assume that only the air needs to be heated and that its volume is 750 m³. Take the specific heat of air to be 0.24 kcal/kg. C°. Express your answer using two significant figures. = 195] ΑΣΦ | 1 Qadded 40756942 → C Submit Previous Answers Request Answer X Incorrect; Try Again; 18 attempts remaining ? J

Elements Of Electromagnetics
Elements Of Electromagnetics
7th Edition
ISBN:9780190698614
Author:Sadiku, Matthew N. O.
Publisher:Sadiku, Matthew N. O.
ChapterMA: Math Assessment
Section: Chapter Questions
Problem 1.1MA
See similar textbooks
icon
Related questions
Question

partb

**Scenario: Heat Transfer in a House** A house has well-insulated walls that are 18.0 cm thick, with a surface area of 450 m². The roof is made of wood, 5.0 cm thick, with an area of 270 m². The house also has uncovered windows that are 0.75 cm thick, with a total area of 34 m². Assume the conductivity of the walls is similar to that of air. **Part A: Heat Loss Calculation** Calculate the rate at which heat must be supplied to maintain an indoor temperature of 22°C when the outside temperature is -15°C. Assume heat is lost only by conduction. - **Solution:** The rate of heat loss by conduction is calculated to be \( Q_{\text{conduction}}/t = 1.6 \times 10^5 \, \text{W} \). The answer is correct. **Part B: Heating the House** Estimate the total heat required to raise the temperature of the house from an initial 10°C to 22°C within 20 minutes. The house has a volume of 750 m³ and only the air inside needs to be heated. The specific heat of air is given as 0.24 kcal/kg·°C. - **Attempt:** The solution entered was \( Q_{\text{added}} = 40756942 \, \text{J} \). This answer is incorrect. Try again; there are 18 attempts remaining.
Transcribed Image Text:**Scenario: Heat Transfer in a House** A house has well-insulated walls that are 18.0 cm thick, with a surface area of 450 m². The roof is made of wood, 5.0 cm thick, with an area of 270 m². The house also has uncovered windows that are 0.75 cm thick, with a total area of 34 m². Assume the conductivity of the walls is similar to that of air. **Part A: Heat Loss Calculation** Calculate the rate at which heat must be supplied to maintain an indoor temperature of 22°C when the outside temperature is -15°C. Assume heat is lost only by conduction. - **Solution:** The rate of heat loss by conduction is calculated to be \( Q_{\text{conduction}}/t = 1.6 \times 10^5 \, \text{W} \). The answer is correct. **Part B: Heating the House** Estimate the total heat required to raise the temperature of the house from an initial 10°C to 22°C within 20 minutes. The house has a volume of 750 m³ and only the air inside needs to be heated. The specific heat of air is given as 0.24 kcal/kg·°C. - **Attempt:** The solution entered was \( Q_{\text{added}} = 40756942 \, \text{J} \). This answer is incorrect. Try again; there are 18 attempts remaining.
Expert Solution
steps

Step by step

Solved in 4 steps with 9 images

SEE SOLUTIONCheck out a sample Q&A here
Blurred answer
Knowledge Booster
Conduction
Learn more about
Need a deep-dive on the concept behind this application? Look no further. Learn more about this topic, mechanical-engineering and related others by exploring similar questions and additional content below.
Recommended textbooks for you
Elements Of Electromagnetics
Elements Of Electromagnetics
Mechanical Engineering
ISBN:
9780190698614
Author:
Sadiku, Matthew N. O.
Publisher:
Oxford University Press
Mechanics of Materials (10th Edition)
Mechanics of Materials (10th Edition)
Mechanical Engineering
ISBN:
9780134319650
Author:
Russell C. Hibbeler
Publisher:
PEARSON
Thermodynamics: An Engineering Approach
Thermodynamics: An Engineering Approach
Mechanical Engineering
ISBN:
9781259822674
Author:
Yunus A. Cengel Dr., Michael A. Boles
Publisher:
McGraw-Hill Education
Control Systems Engineering
Control Systems Engineering
Mechanical Engineering
ISBN:
9781118170519
Author:
Norman S. Nise
Publisher:
WILEY
Mechanics of Materials (MindTap Course List)
Mechanics of Materials (MindTap Course List)
Mechanical Engineering
ISBN:
9781337093347
Author:
Barry J. Goodno, James M. Gere
Publisher:
Cengage Learning
Engineering Mechanics: Statics
Engineering Mechanics: Statics
Mechanical Engineering
ISBN:
9781118807330
Author:
James L. Meriam, L. G. Kraige, J. N. Bolton
Publisher:
WILEY
SEE MORE TEXTBOOKS