-Z/Zo 3 The density of air as a function of altitude above sea level is modeled as p(z) = poe` where po = 1.2 kg/m³, and zo = 16, 855 m. A spherical balloon with radius r = 0.2 m is filled with Helium gas (MH₂ = 4 g/mol) to STP (P = 1 atm, T = 273 K). What is the maximum height the balloon can float up to assuming constant pressure and temperature within the balloon? Assume that the density of air is constant across the volume of the balloon for a specific height, and that the balloon's rubber has negligible mo

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
icon
Related questions
Question

**see image for question**

**Density of Air as a Function of Altitude**

The density of air as a function of altitude above sea level is modeled as:

\[ \rho(z) = \rho_0 e^{-z/z_0} \]

where:
- \( \rho_0 = 1.2 \, \text{kg/m}^3 \)
- \( z_0 = 16,855 \, \text{m} \)

A spherical balloon with a radius of \( r = 0.2 \, \text{m} \) is filled with Helium gas (\( M_{\text{He}} = 4 \, \text{g/mol} \)) to STP (\( P = 1 \, \text{atm} \), \( T = 273 \, \text{K} \)). 

**Problem Statement:**
What is the maximum height the balloon can float up to, assuming constant pressure and temperature within the balloon? Assume that the density of air is constant across the volume of the balloon for a specific height, and that the balloon’s rubber has negligible mass.


**Step-by-Step Solution:**

1. **Calculate Volume of the Balloon:**

   The volume \( V \) of a sphere is given by:
   
   \[
   V = \frac{4}{3} \pi r^3
   \]
   
   Substituting \( r = 0.2 \, \text{m} \):
   
   \[
   V = \frac{4}{3} \pi (0.2)^3 \approx 0.0335 \, \text{m}^3
   \]

2. **Determine the Mass of Helium in the Balloon:**

   Using the Ideal Gas Law \( PV = nRT \), where \( R \) is the gas constant (\( 8.314 \, \text{J/(mol} \cdot \text{K)} \)):
   
   \[
   n = \frac{PV}{RT}
   \]
   
   Given \( P = 1 \, \text{atm} = 101325 \, \text{Pa} \) and \( T = 273 \, \text{K} \):
   
   \[
   n = \frac{101325 \times 0.0335}{8.314 \times 273} \approx 1.49
Transcribed Image Text:**Density of Air as a Function of Altitude** The density of air as a function of altitude above sea level is modeled as: \[ \rho(z) = \rho_0 e^{-z/z_0} \] where: - \( \rho_0 = 1.2 \, \text{kg/m}^3 \) - \( z_0 = 16,855 \, \text{m} \) A spherical balloon with a radius of \( r = 0.2 \, \text{m} \) is filled with Helium gas (\( M_{\text{He}} = 4 \, \text{g/mol} \)) to STP (\( P = 1 \, \text{atm} \), \( T = 273 \, \text{K} \)). **Problem Statement:** What is the maximum height the balloon can float up to, assuming constant pressure and temperature within the balloon? Assume that the density of air is constant across the volume of the balloon for a specific height, and that the balloon’s rubber has negligible mass. **Step-by-Step Solution:** 1. **Calculate Volume of the Balloon:** The volume \( V \) of a sphere is given by: \[ V = \frac{4}{3} \pi r^3 \] Substituting \( r = 0.2 \, \text{m} \): \[ V = \frac{4}{3} \pi (0.2)^3 \approx 0.0335 \, \text{m}^3 \] 2. **Determine the Mass of Helium in the Balloon:** Using the Ideal Gas Law \( PV = nRT \), where \( R \) is the gas constant (\( 8.314 \, \text{J/(mol} \cdot \text{K)} \)): \[ n = \frac{PV}{RT} \] Given \( P = 1 \, \text{atm} = 101325 \, \text{Pa} \) and \( T = 273 \, \text{K} \): \[ n = \frac{101325 \times 0.0335}{8.314 \times 273} \approx 1.49
### Thermal Properties of Various Materials

Below is a table summarizing the thermal properties of several materials. This information is crucial in understanding how different substances respond to changes in temperature, including their heat capacities, latent heats, and densities. 

| Material            | α (°C⁻¹)     | c (J/(kg K))  | C (J/(mol K))  | Lf (J/kg)    | Lv (J/kg)    | Density (kg/m³) |
|-----------------|------------------|----------------|------------------|----------------|-----------------|--------------------|
| Gold                  | -                              | 129                        | 25                      | -                          | -                          | 19,300               |
| Copper              | 1.65×10⁻⁵            | -                            | -                         | -                          | -                          | 8,960                 |
| Aluminum           | 2.3×10⁻⁵              | -                            | -                         | -                          | -                          | 2,700                 |
| Stainless Steel    | 1.75×10⁻⁵            | -                            | -                         | -                          | -                          | 7,500                 |
| Water                | -                             | 4190                     | 75                     | 3.33×10⁵            | 22.6×10⁵             | 1,000                |
| Ethyl Alcohol     | -                             | 2400                     | 110                      | 1.09×10⁵           | 8.79×10⁵             | 790                   |
| Ice                      | -                            | 2090                     | 37.6                     | -                           | -                          | 917                   |

### Constants
- **1 atm = 1.01×10⁵ Pa**
- **Nᴀ = 6.022×10²³ particles/mol**
- **R = 8.3145 J/(mol K)**
- **kB = 1.38×10⁻²³ J/K**
- **σ = 5.67×10⁻⁸ W/(m²K⁴)**

### Explanation of Columns:
- **α (°C⁻¹)**: The coefficient of linear thermal expansion, showing how much the material expands per degree Celsius increase in temperature.
- **c (J/(kg K))**: The
Transcribed Image Text:### Thermal Properties of Various Materials Below is a table summarizing the thermal properties of several materials. This information is crucial in understanding how different substances respond to changes in temperature, including their heat capacities, latent heats, and densities. | Material | α (°C⁻¹) | c (J/(kg K)) | C (J/(mol K)) | Lf (J/kg) | Lv (J/kg) | Density (kg/m³) | |-----------------|------------------|----------------|------------------|----------------|-----------------|--------------------| | Gold | - | 129 | 25 | - | - | 19,300 | | Copper | 1.65×10⁻⁵ | - | - | - | - | 8,960 | | Aluminum | 2.3×10⁻⁵ | - | - | - | - | 2,700 | | Stainless Steel | 1.75×10⁻⁵ | - | - | - | - | 7,500 | | Water | - | 4190 | 75 | 3.33×10⁵ | 22.6×10⁵ | 1,000 | | Ethyl Alcohol | - | 2400 | 110 | 1.09×10⁵ | 8.79×10⁵ | 790 | | Ice | - | 2090 | 37.6 | - | - | 917 | ### Constants - **1 atm = 1.01×10⁵ Pa** - **Nᴀ = 6.022×10²³ particles/mol** - **R = 8.3145 J/(mol K)** - **kB = 1.38×10⁻²³ J/K** - **σ = 5.67×10⁻⁸ W/(m²K⁴)** ### Explanation of Columns: - **α (°C⁻¹)**: The coefficient of linear thermal expansion, showing how much the material expands per degree Celsius increase in temperature. - **c (J/(kg K))**: The
Expert Solution
steps

Step by step

Solved in 2 steps with 1 images

Blurred answer
Knowledge Booster
Elastic Constants and Their Relationship
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.
Similar questions
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