1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
Tomtit [17]
3 years ago
7

A hydrogen-filled balloon to be used in high altitude atmosphere studies will eventually be 100 ft in diameter. At 150,000 ft, t

he pressure is 0.14 lb/in2 and the temperature is - 67°F. Assume the balloon is spherical in shape. What is the diameter of the hydrogen balloon at the ground at 14.7 lb/in2 and 68°F
Engineering
1 answer:
max2010maxim [7]3 years ago
5 0

Answer:

The answer is 11.7 ft

Explanation:

You can use the combined gas law from Boyle's law, Charles's law, and Gay-Lussac's Law. Only because hydrogen behaves like an ideal gas for this conditions.

\frac{p_1 V_1}{T_1} = \frac{p_2 V_2}{T_2}

where the subscripts denote the pressure "p", volume "V" and the temperature "T" (in Kelvin) at two different times. Let's consider t_1 as the balloom at 150,000 ft so

p_1 = 0.14 \ lb/in^2

V_1 = \frac{4}{3} \pi R_1^3 = 523598.77 \ ft^3

and T_1 = -67^\circ F = 218.15\ K.

Then, t_2 is the moment when the balloon is on the ground.

p_2 = 14.7 \ lb/in^2 and  T_2 = 68^\circ F = 293.15\ K.

From the first equation,

V_2 = \frac{p_1 V_1 T_2}{T_1 p_2}, then

V_2 = 6701.07 ft^3 and the radius would be  

R_2 = \sqrt[3]{\frac{3 V_2}{4 \pi}} = 11.7 \ ft.

You might be interested in
A sphere is assumed to have the properties of water and has an initial heat generation 46480 W/m^3 How much should the heat gene
Verdich [7]

Answer:

Resulting heat generation, Q = 77.638 kcal/h

Given:

Initial heat generation of the sphere, Q_{Gi} = 46480 W/m^{3}

Maximum temperature, T_{m} = 360 K

Radius of the sphere, r = 0.1 m

Ambient air temperature, T = 25^{\circ}C = 298 K

Solution:

Now, maximum heat generation, Q_{m} is given by:

T_{m} = \frac{Q_{m}r^{2}}{6K} + T                     (1)

where

K = Thermal conductivity of water at T_{m} = 360 K = 0.67 W/m^{\circ}C

Now, using eqn (1):

360 = \frac{Q_{m}\times 0.1^{2}}{6\times 0.67} + 298

Q_{m} = 24924 W/m^{3}

max. heat generation at maintained max. temperature of 360 K is 24924W/m^{3}

For excess heat generation, Q:

Q = (Q_{Gi} - Q_{m})\times volume of sphere, V

where

V = \frac{4}{3}\pi r^{3}

Q = (46480 - 24924)\times \frac{4}{3}\pi\0.1^{3} = 21556\times \frac{4}{3}\pi\0.1^{3} W/m^{3}

Q = 90.294 W

Now, 1 kcal/h = 1.163 W

Therefore,

Q = \frac{90.294}{1.163} = 77.638 kcal/h

3 0
2 years ago
Air at 25ºC flows in an electric hair drier with a velocity of 6 m/s perpendicular to a Nichrome heating element. The heating el
Hunter-Best [27]

Answer:

Check the explanation

Explanation:

Electrical current can be measured according to the rate of electric charge flow in any electrical circuit:

i(t) = dQ(t) / dt

the derivative of the electric charge by time determines the momentary current.

i(t) will be the momentary current I at time t in amps (A).

Q(t) will also be the momentary electric charge in coulombs (C).

t is the time in seconds (s).

so if the current is constant:

I = ΔQ / Δt

I will be the current in amps (A).

ΔQ will be the electric charge in coulombs (C), which is expected to flows at time duration of Δt.

Δt is the time duration in seconds (s).

Kindly check the attached image below to get the step by step explanation to the question above.

3 0
3 years ago
Evaluate to three significant figures and using appropriate prefix: (354 mg)(45 km)/(0.0356 kN)
frutty [35]

Answer:

0.447 s²

Explanation:

First, convert to SI units.

(354 mg) (45 km) / (0.0356 kN)

(0.354 g) (45000 m) / (35.6 N)

One Newton is kg m/s²:

(0.354 g) (45000 m) / (35.6 kg m/s²)

(0.000354 kg) (45000 m) / (35.6 kg m/s²)

Simplify:

0.447 s²

5 0
3 years ago
What is the value of the magicPowers variable after executing the following code snippet? String magicPowers = ""; int experienc
Evgen [1.6K]

Answer:

Shining lantern Magic beans                

Explanation:

I will explain the code line by line.

The first statement contains a string type variable magicPowers and second statement has an int type variable experienceLevel which is initialized by value 9.

Nested if statement are used and lets see which of those statements execute.

The first if statement checks if the value of experienceLevel is greater than 10. This statement evaluates to false because the value of experienceLevel is set to 9. Then the program control moves to the next if statement.

The second if statement checks if the value of experienceLevel is greater than 8. This if condition evaluates to true because the value of experienceLevel  is 9. So this if statement is executed which contains the statement magicPowers = magicPowers + "Shining lantern "; . This means magicPowers stores the string Shining lantern.

The third if statement checks if the value of experienceLevel  is greater than 2. As the value of experienceLevel  is 9 so this condition also evaluates to true which means the statement magicPowers = magicPowers + "Magic beans "; is executed. This statement means magicPowers stores the string Magic Beans

You can use a print statement to display the output on the screen as:

System.out.print(magicPowers);

Output:

Shining lantern Magic beans        

The program along with the output is attached as a screenshot.

5 0
3 years ago
Mobility refers to the ability to?
aev [14]

Answer:

Drive

Explanation:

Drive is a great example

4 0
3 years ago
Other questions:
  • An unknown immiscible liquid seeps into the bottom of an open oil tank. Some measurements indicate that the depth of the unknown
    12·1 answer
  • A material has the following properties: Sut = 275 MPa and n = 0.40. Calculate its strength coefficient, K.
    14·1 answer
  • A 3-phase, 50 Hz, 110 KV overhead line has conductors placed in a horizontal plane 3 m apart. Conductor diameter is 2.5 cm. If t
    6·1 answer
  • A hawser is wrapped two full turns around a bollard. By exerting an 80-lb force on the free end of the hawser, a dockworker can
    6·1 answer
  • Miles (322,000 kilometers [km]) or
    12·2 answers
  • Pls hurry
    6·1 answer
  • Which of these fuel injection systems operates with fuel injectors located only in the intake manifold near each intake
    14·1 answer
  • What are the materials and tools used to build a headgear?​
    5·1 answer
  • 17. Swing arm restraints are intended to prevent a vehicle from falling off a lift.
    6·1 answer
  • Please look at the picture for question.
    14·2 answers
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!