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
barxatty [35]
3 years ago
6

You’ve experienced convection cooling if you’ve ever extended your hand out the window of a moving vehicle or into a flowing wat

er stream. With the surface of your hand at a temperature of 30°C, consider the two following conditions.
Condition A: a vehicle speed of 35 km/h in air at -5°C with a convection coefficient of 40 W/m2·K.
Condition B: a velocity of 0.2 m/s in a water stream at 10°C with a convection coefficient of 800 W/m2·K.

What is the convection heat flux for these two condition?
Engineering
1 answer:
Anna35 [415]3 years ago
7 0

Answer:

Condition A

Heat flux is 1400 W/M^2

Condition B

Heat flux is 12800 w/m^2

Explanation:

Given that:

T_s is given as  30 degree celcius

condition A

Air temperature =  - 5 degree c

convection coefficient h = 40 w/m^2. k

heat\ flux = \frac{Q}{a}= h\Delta = 40{30 - (-5)} = 1400 w/m^2

condition A

water temperature  = 10 degree c

convection coefficient = 800 w/m^2.k

heat\ flux = \frac{Q}{A} = H(\Delta} = 800\times (30-14) = 12800w/m^2

You might be interested in
How to code the round maze in CoderZ?
dlinn [17]

Answer:

hola

Explanation:

5 0
3 years ago
If you get a flat in the front of your car, your car will:
juin [17]

Answer:

stop and might even crash

Explanation:

6 0
2 years ago
A room is kept at −5°C by a vapor-compression refrigeration cycle with R-134a as the refrigerant. Heat is rejected to cooling wa
Fed [463]

Answer:

note:

<u>solution is attached in word form due to error in mathematical equation. furthermore i also attach Screenshot of solution in word due to different version of MS Office please find the attachment</u>

Download docx
4 0
3 years ago
Read 2 more answers
A 1000 W iron utilizes a resistance wire which is 20 inches long and has a diameter of 0.08 inches. Determine the rate of heat g
SSSSS [86.1K]

Answer:

The rate of heat generation in the wire per unit volume is 5.79×10^7 Btu/hrft^3

Heat flux is 9.67×10^7 Btu/hrft^2

Explanation:

Rate of heat generation = 1000 W = 1000/0.29307 = 3412.15 Btu/hr

Area (A) = πD^2/4

Diameter (D) = 0.08 inches = 0.08 in × 3.2808 ft/39.37 in = 0.0067 ft

A = 3.142×0.0067^2/4 = 3.53×10^-5 ft^2

Volume (V) = A × Length

L = 20 inches = 20 in × 3.2808 ft/39.37 in = 1.67 ft

V = 3.53×10^-5 × 1.67 = 5.8951×10^-5 ft^3

Rate of heat generation in the wire per unit volume = 3412.15 Btu/hr ÷ 5.8951×10^-5 ft^3 = 5.79×10^7 Btu/hrft^3

Heat flux = 3412.15 Btu/hr ÷ 3.53×10^-5 ft^2 = 9.67×10^7 Btu/hrft^2

3 0
3 years ago
Consider a resistor made of pure silicon with a cross-sectional area pf 0.5 μm2, and a length of 50 μm. What is the resistance o
lukranit [14]

Answer: 24 pA

Explanation:

As pure silicon is a semiconductor, the resistivity value is strongly dependent of temperature, as the main responsible for conductivity, the number of charge carriers (both electrons and holes) does.

Based on these considerations, we found that at room temperature, pure silicon resistivity can be approximated as 2.1. 10⁵  Ω  cm.

The resistance R of a given resistor, is expressed by the following formula:

R = ρ L / A

Replacing by the values for resistivity, L and A, we have

R = 2.1. 10⁵ Ω  cm. (10⁴ μm/cm). 50 μm/ 0.5 μm2

R = 2.1. 10¹¹ Ω

Assuming that we can apply Ohm´s Law, the current that would pass through this resistor for an applied voltage of 5 V, is as follows:

I = V/R = 5 V / 2.1.10¹¹ Ω = 2.38. 10⁻¹¹ A= 24 pA

7 0
3 years ago
Other questions:
  • A 356 cast aluminum test bar is tested in tension. The initial gage length as marked on the sample is 50mm and the initial diame
    9·1 answer
  • A gasoline engine has a piston/cylinder with 0.1 kg air at 4 MPa, 1527◦C after combustion, and this is expanded in a polytropic
    14·1 answer
  • james wants to qualify for icp are and licensure. Which degree would be required in order to qualify for a two year master of ar
    15·1 answer
  • The products of combustion from a burner are routed to an industrial application through a thin-walled metallic duct of diameter
    11·1 answer
  • What are probiotic bacteria and how did Danino and his team use this type of bacteria to detect liver cancer?
    15·1 answer
  • A river has an average rate of water flow of 59.6 M3/s. This river has three tributaries, tributary A, B and C, which account fo
    10·1 answer
  • How buy airpods in my phone​
    7·2 answers
  • How do you breed a linner?
    5·2 answers
  • Why is it important to follow the engineering design process before building a prototype
    13·1 answer
  • What is the tolerance of number 4?
    12·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!