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
Svetach [21]
3 years ago
11

A 2-mm-diameter electrical wire is insulated by a 2-mm-thick rubberized sheath (k = 0.13 W/m K), and the wire/sheath interface i

s characterized by a thermal contact resistance of R"t,c= 3x10-4 m2 K/W. The convection heat transfer coefficient at the outer surface of the sheath is 10 W/m2 K, and the temperature of the ambient air is 20o C. If the temperature of the insulation may not exceed 50o C, what is the maximum allowable electrical power that may be dissipated per unit length of the conductor? What is the critical radius of the insulation?

Engineering
1 answer:
Semmy [17]3 years ago
3 0

Answer:

maximum allowable electrical power=4.51W/m

critical radius of the insulation=13mm

Explanation:

Hello!

To solve this heat transfer problem we must initially draw the wire and interpret the whole problem (see attached image)

Subsequently, consider the heat transfer equation from the internal part of the tube to the external air, taking into account the resistance by convection, and  conduction as shown in the attached image

to find the critical insulation radius we must divide the conductivity of the material by the external convective coefficient

r=\frac{k}{h} =\frac{0.13}{10}=0.013m=13mm

You might be interested in
A power company desires to use groundwater from a hot spring to power a heat engine. If the groundwater is at 95 deg C and the a
prisoha [69]

Answer:

W  = 12.8 KW

Explanation:

given data:

mass flow rate = 0.2 kg/s

Engine recieve heat from ground water at 95 degree ( 368 K)  and reject that heat to atmosphere  at 20 degree (293K)

we know that maximum possible efficiency is given as

\eta = 1- \frac{T_L}{T_H}

\eta = 1 - \frac{ 293}{368}

\eta = 0.2038

rate of heat transfer is given as

Q_H = \dot m C_p \Delta T

Q_H = 0.2 * 4.18 8(95 - 20)

Q_H = 62.7 kW

Maximuim power is given as

W = \eta Q_H

W = 0.2038 * 62.7

W  = 12.8 KW

3 0
3 years ago
Identify the different engineering activities/steps in the engineering design process for each steps,summarize in 1–3 sentences
Gennadij [26K]

Answer:

Hi how are you doing today Jasmine

5 0
3 years ago
Give me uses of a grinding machine in agriculture.
Tju [1.3M]

Answer:

The grinding machine is used for roughing and finishing flat, cylindrical, and conical surfaces; finishing internal cylinders or bores; forming and sharpening cutting tools; snagging or removing rough projections from castings and stampings; and cleaning, polishing, and buffing surfaces.

4 0
3 years ago
(Signal Property) Under what condition is a discrete-time signal x[????] or a continuous-time signal x(????) periodic? Determine
Cloud [144]

Answer:

a. 2x/3

b. 8

Explanation:

fundamental period can be defined to mean that at after every period of 2π radians or 360° the value of graph is repeated. For such functions the fundamental period is the period after which they repeat themselves.

It van also be looked as The fundamental period of cos(θ) is 2π. That is (for example) cos(0) to cos(2π) represents one full period.

Please see attachment for the step by step solution.

7 0
3 years ago
Harlin is designing a new car engine that does not create pollution. Which technological design factor is probably the most
kari74 [83]

Answer: environmental impact

Explanation:

From the question, we are informed that Harlin is designing a new car engine that does not create pollution.

The technological design factor which is probably the most important for the design is the impact on the environment.

Pollution has a negative effect on the environment a d doing this shows that emphasis is placed on how the environmental issue of pollution can be tackled.

8 0
3 years ago
Other questions:
  • 1. Create a class called Name that represents a person's name. The class should have fields named firstName representing the per
    8·2 answers
  • Describe the steps, tools, and technology needed in detail and
    12·1 answer
  • A groundwater contains the following cations (expressed as the cation):
    5·2 answers
  • A sludge pump pumps at a rate of 40 GPM. The raw sludge density is 4.5 percent solids. How many minutes per hour should the pump
    11·1 answer
  • By using a book of the OHS Act, Act 85 of 1993, find the act or regulation where the following extraction comes from "every empl
    12·1 answer
  • Think about the KIA factory shown in the video, what are two things that managers could do to reduce waste or increase efficienc
    6·1 answer
  • There is a black-box system (i.e we do not know the transfer function of the system). When we fed a step input into the system,
    9·1 answer
  • Two children are playing on a seesaw. The child on the left weighs 50 lbs. And the child on the right weighs 100 lbs. If the chi
    5·1 answer
  • Name eight safety electrical devices including their functions and effects if not present.​
    15·1 answer
  • Which of the following is NOT one of the 3 technology bets we have made?
    15·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!