A 0.091-in-diameter electrical wire at 90°F is covered by 0.02-in-thick plastic insulation (k = 0.075 Btu/h·ft·°F). The wire is exposed to a medium at 50°F, with a combined convection and radiation heat transfer coefficient of 2.5 Btu/h·ft2·°F. Calculate the critical radius (rcr) of the plastic insulation (in inches).

Answers

Answer 1

Answer:

The critical radius of the plastic insulation is 0.72 inches.

Explanation:

Given that,

Diameter = 0.091 in

Thickness = 0.02 in

Initial temperature = 90°F

Final temperature = 50°F

Heat transfer coefficient = 2.5 Btu/h.ft²°F

Material conductivity = 0.075 Btu/h.ft °F

We need to calculate the critical radius of the plastic insulation

Using formula of critical radius

[tex]r_{cr}=\dfrac{2K}{h}[/tex]

Where, k = Material conductivity

h = Heat transfer coefficient

Put the value into the formula

[tex]r_{cr}=\dfrac{2\times0.075}{2.5}[/tex]

[tex]r_{cr}=0.06\ ft[/tex]

[tex]r_{cr}=0.72\ inches[/tex]

Hence, The critical radius of the plastic insulation is 0.72 inches.


Related Questions

An electron enters a region of uniform electric field with an initial velocity of 64 km/s in the same direction as the electric field, which has magnitude E = 48 N/C. (a) What is the speed of the electron 1.3 ns after entering this region? (b) How far does the electron travel during the 1.3 ns interval?

Answers

Answer:

1.) 11 km/s

2.) 9.03 × 10^-5 metres

Explanation:

Given that an electron enters a region of uniform electric field with an initial velocity of 64 km/s in the same direction as the electric field, which has magnitude E = 48 N/C.

Electron q = 1.6×10^-19 C

Electron mass = 9.11×10^-31 Kg

(a) What is the speed of the electron 1.3 ns after entering this region?

E = F/q

F = Eq

Ma = Eq

M × V/t = Eq

Substitute all the parameters into the formula

9.11×10^-31 × V/1.3×10^-9 = 48 × 1.6×10^-19

V = 7.68×10^-18 /7.0×10^-22

V = 10971.43 m/s

V = 11 Km/s approximately

(b) How far does the electron travel during the 1.3 ns interval?

The initial velocity U = 64 km/s

S = ut + 1/2at^2

S = 64000×1.3×10^-6 + 1/2 × 8.4×10^12 × ( 1.3×10^-9)^2

S =8.32×10^-5 + 7.13×10^-6

S = 9.03 × 10^-5 metres

What is normalization ​

Answers

Answer:

Normalization is a systematic approach of decomposing tables to eliminate data redundancy. It is a multi-step process that puts data into tabular form, removing duplicated data from the relation tables.

Explanation:

Answer:

the process of bringing or returning something to a normal condition or state.

Explanation:

In "your own words"- Normalization is when you change something back into it's average form.

the graph shows position versus time for an object moving with the constant acceleration. what is the final velocity of the object at t=10s? assume the initial velocity at the origin is 1 m/s.

3.32 m/s
4.0 m/s
3.0 m/s
3.8 m/s

Answers

Answer:

  3.0 m/s

Explanation:

The equation of motion for constant acceleration (a) is ...

  [tex]x(t)=\dfrac{1}{2}at^2 +v_0t+x_0[/tex]

The problem statement tells us v₀ = 1, and we read from the graph that x₀=1. We also read from the graph that x(10) = 21. Filling these values into the equation, we can find a and x'(10).

  [tex]21 = \dfrac{1}{2}a(10^2)+1(10)+1\\\\10=50a\qquad\text{subtract 11}\\\\a=\dfrac{1}{5}\\\\x'(t)=at+v_0\\\\x'(10)=\dfrac{1}{5}\cdot 10+1=3.0[/tex]

The final velocity of the object at t=10 s is about 3.0 m/s.

_____

Comment on the graph

We note this graph better represents increasing acceleration than it does constant acceleration. x(2) = 3.4 per the equation. It is graphed as about 4.

Answer:

thanks for de points

Explanation:

what type of organism does not use photosynthesis
(a) plants
(b) bacteria
(c) algae
(d) humans

Answers

Answer:

D) Humans

Explanation:

Photosynthesis is a useless ability without some way of exposing yourself to as much of the Sun's energy as possible. That requires a large surface area, relative to their volume. Plants achieve that with large, horizontal, light-capturing surfaces – leaves.

Which has the fastest wave speed, a high frequency sound or a low frequency sound?

Answers

Answer:

high frequent sound

Explanation:

because if its low than its slower.

Which is a benefit of using synthetic polymers, such as nylon?
Synthetic polymers are lightweight.
O Synthetic polymers are produced in small
quantities.
Synthetic polymers are biodegradable.
Synthetic polymers are inexpensive to recycle.

Answers

Answer: Synthetic polymers are lightweight.

Explanation:

A  benefit of using synthetic polymers is the fact that synthetic polymers are lightweight.

A polymer is a molecule composed of many repeating subunits.

Synthetic polymers are artificial polymers created by humans.

Most of the synthetic polymers are not biodegradable (unlike natural fibers such as cotton).

Synthetic polymers are classified according to their use into plastics, elastomers and synthetic fibers.

The advantages of synthetic polymers include: hard to break, being lightweight, and they last for a long time.

In conclusion, a benefit of using synthetic polymers is the fact that synthetic polymers are lightweight.

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A classroom is about 3 meters high, 20 meters wide and 30 meters long. If the density of air is 1.29 kg/m3, what is the mass of the air in the classroom?

Answers

Answer:

the mass of the air in the classroom = 2322 kg

Explanation:

given:

A classroom is about 3 meters high, 20 meters wide and 30 meters long.

If the density of air is 1.29 kg/m3

find:

what is the mass of the air in the classroom?

density = mass / volume

where mass (m) = 1.29 kg/m³

volume = 3m x 20m x 30m = 1800 m³

plugin values into the formula

  1.29 kg/m³   =        mass    

                             1800 m³

mass =  1.29 kg/m³  ( 1800 m³ )

mass = 2322 kg

therefore,

the mass of the air in the classroom = 2322 kg

If A classroom is about 3 meters high, 20 meters wide and 30 meters long. If the density of air is 1.29 kg/m3, then the mass of the air in the classroom is 2322Kg.

What is density??

Density is the ratio of mass to volume. it tells how much mass a body is having for its unit volume. for example egg yolk has 1027kg/m³ of density, means if we collect numbers of egg yolk and keep it in a container having volume 1 m³ then total amount of mass it is having will be 1027kg. Density is a scalar quantity. when we add egg yolk into the water, egg yolk has greater density than water( 997 kg/m³), because of higher density of egg yolk it contains higher mass in same volume as water. hence due to higher mass higher gravitational force is acting on the egg yolk therefore it goes down on the inside the water. water will float upon the egg yolk. same situation we have seen when we spread oil in the water. ( in that case water has higher density than oil. thats why oil floats on the water).

Given,

Height = 3 m

Width = 20 m

length= 30 m

Density of air = 1.29kg/m³

The  volume of the room = 3×20×30 m³

Volume V = 1800m³

By formula,

Density = Mass/Volume

1.29kg/m³ = Mass/1800m³

Mass of the air = 1.29×1800 = 2322 Kg

The mass of the air is classroom is 2322Kg.

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Oppositely charged parallel plates are separated by 4.49 mm. A potential difference of 600 V exists between the plates. (a) What is the magnitude of the electric field between the plates? N/C (b) What is the magnitude of the force on an electron between the plates? N (c) How much work must be done on the electron to move it to the negative plate if it is initially positioned 3.14 mm from the positive plate?

Answers

Answer:

A. Using

E=V/d

= 600/4.49*10^-3

= 1.336 x10^5 N/C

b) F = E*q = 1.33610^5 x 1.6*10^-19

= 2.17 x 10^-14 N

c) Work = Fs distance = 2.17 x 10^-14 N (4.49-3.14)*.001= 1.35 x 10^-17 J

what role do control groups play

Answers

Answer:

Control groups let the one who is expermenting compare  the effect of the varibles in the expermental group.

Explanation:

A car travels 82 meters do North and 14 seconds the car turns around and travels 44 m due south in four seconds what is the magnitude of the average velocity of the car during the full travel time?

Answers

Answer:

2.11 m/s

Explanation:

Take north to be positive and south to be negative.

Average velocity = displacement / time

v = (82 m + -44 m) / (14 s + 4 s)

v = 2.11 m/s

The velocity is positive, so it is 2.11 m/s north.  The magnitude of the velocity is 2.11 m/s.

A cyclist accelerates from rest to 8 m/s in 3 seconds. How far did the cycles travel in 3 seconds?​

Answers

Answer:

[tex] \boxed{\sf Distance \ travelled = 12 \ m} [/tex]

Given:

Initial speed (u) = 0 m/s (Accelerates from rest)

Final speed (v) = 8 m/s

Time taken (t) = 3 seconds

To Find:

Distance travelled by cyclist (s)

Explanation:

From equation of motion of object moving with uniform acceleration in straight line we have:

[tex] \boxed{ \bold{s = (\frac{v + u}{2} )t}}[/tex]

By substituting value of v, u & t in the equation we get:

[tex] \sf \implies s = ( \frac{8 + 0}{2} ) \times 3 \\ \\ \sf \implies s = \frac{8}{2} \times 3 \\ \\ \sf \implies s = 4 \times 3 \\ \\ \sf \implies s = 12 \: m[/tex]

[tex] \therefore[/tex]

Distance travelled by cyclist (s) = 12 m

Answer:

s(distance) =36m

Explanation:

u(initial velocity) =0 m/s

a =8 m/s^2

t=3s

s=ut+1/2at^2

s=1/2(8)(3)^2

s=1/2(8)(3)(3)

s=4(9)

s=36m

How did oxygen get into the earths atmosphere in its early days? plz explain

Answers

Answer:

The answer is tiny organisms known as cyanobacteria, or blue-green algae. These microbes conduct photosynthesis: using sunshine, water and carbon dioxide to produce carbohydrates and, yes, oxygen. In fact, all the plants on Earth incorporate symbiotic cyanobacteria (known as chloroplasts) to do their photosynthesis for them down to this day.

Explanation:

The group that receives treatment is called the?
Tested Group
Control Group
Placebo Group
Experimental Group

Answers

Answer:

experimental group

Explanation:

please mark me as a brainlist..

Answer:

Experemtial group

Explanation:

The placebo is just sugar pills tested is ones already done and control is a mix of the two

5. Why does a properly adjusted head restraint help prevent head and neck injuries to occupants in
rear-end collisions? Explain your answer in terms of the law of conservation of momentum.

Answers

Answer:

Have you tried google

Explanation:

Answer:

protect against whisplasg injuries

What is a statement ?

Answers

A statement is a definite or clear expression of something in speech or writing.

I need with the basic understanding of this​

Answers

Answer:

A = air resistance

B = lift

C = thrust

D = gravity

1.00 N, 2.86° above horizontal

Explanation:

Gravity pulls down on the bird.  The thrust of the birds wings push it forward, and the lift pushes it up.  Air resistance pushes it back.

The net force in the y direction is:

∑Fᵧ = lift − gravity

∑Fᵧ = 0.20 N − 0.15 N

∑Fᵧ = 0.05 N

The net force in the x direction is:

∑Fₓ = thrust − air resistance

∑Fₓ = 1.50 N − 0.50 N

∑Fₓ = 1.00 N

The magnitude of the resultant force is:

F² = Fₓ² + Fᵧ²

F² = (1.00 N)² + (0.05 N)²

F ≈ 1.00 N

The direction of the resultant force is:

tan θ = Fᵧ / Fₓ

tan θ = (0.05 N) / (1.00 N)

θ = 2.86° above horizontal

- When a mixture contains substances that are not evenly mixed, it is called?

Answers

Answer:  Heterogenous mixture

Explanation:

A heterogeneous mixture in which the components of the mixture are not evenly mixed or uniform, allowing one to identify the different constituents of each components and enable the mixture to be separated physically.

Examples of heterogeneous mixtures includes

-- sand and nails

---rice and beans

--- water and oil

Another type of mixture is the homogeneous mixture in which all the components are evenly mixed causing that each components cannot be visible with the eye and therefore separated chemically.

The chilled water system for a 27-story building has a pump located at ground level. The lost head in a vertical riser from the pump to an equipment room on the twenty-seventhfloor is 40ftof water, and the pump produces 270ft of head. What is the pressure on the suction side of the pump for a pressure of 8 psig to exist in the riser on the twenty-fifth floor

Answers

This question is incomplete, the complete question is;

The chilled water system for a 27-story building has a pump located at ground level. The lost head in a vertical riser from the pump to an equipment room on the twenty-seventh floor is 40ft of water, and the pump produces 270ft of head. What is the pressure on the suction side of the pump for a pressure of 8 psig to exist in the riser on the twenty-fifth floor

Assume 12ft of elevation per floor

Answer: 48.68 psig

Explanation:

First  we calculate the elevation of the building

hb = 27 story * 12ft per floor/story

hb =  324 ft

given that the head lost in the vertical riser hL = 40 ft

now the delivery head required in the riser on he 27th floor;

hd = 8 psig *  (2.31 ft / 1 psig)

hd = 18.46 ft

Now calculate the suction head required by balancing the energy per unit weight of water, considering pump as the control volume

hp = (hb + hL + hd) - hs

hs = hb + hL + hd - hp

where hp is the head developed by the pump (270 ft)

hb is the elevation of the 27th floor of the building ( 324 ft)

hL is the head lost in the vertical riser ( 40 ft)

hd is the head required to exist in the riser on the 27th floor (18.46 ft)

so we substitute

hs = 324 ft + 40 ft + 18.46 ft - 270 ft

hs = 112.46

so 112.46ft * (1 psig / 2.31 ft)

= 48.68 psig

One of the specific goals of of environmental analysis is:____________
a: To provide organized information, for the development of the organization's internal analysis, mission, vision , values and strategy.
b: To measure organizational efficiency.
c: To ignore minor competitors.
d: To develop a list of "one-word: descriptions of the external environment.

Answers

Answer:

a: To provide organized information, for the development of the organization's internal analysis, mission, vision, values, and strategy.

Explanation:

Environmental analysis is a process in business wherein the internal and external factors that can affect a business are examined so as to help improve the organization's goals and strategies. The internal analysis serves as a guide to checkmate the organization and to see if they have adopted the right strategies that suit their external environment.

Competitors in the external environment can have a huge impact on the business. So the internal workings of the organization should align with the external factors. The organized information would also be useful in forecasting the growth of the business.          

The Shinkansen (bullet train in Japan) makes a trip from Tokyo Station to Kyoto station in 2 hours and 14 min. The distance traveled is 460 km (to two significant figures). Determine the average velocity of the train in meters per second (m/s). [conversions: 1 km = 1000 m, 1 hr = 60 min, 1 min = 60 s] *

Answers

Answer:

v =  57.2 m/s

Explanation:

The average velocity of the train can be defined as the total distance covered by the train divided by the time taken by the train to cover that distance. Therefore, we will use the following formula to find the average velocity of the train:

v = s/t

where,

s = distance covered = 460 km = (460 km)(1000 m/1 km) = 4.6 x 10⁵ m

t = time taken to cover the distance = 2 h 14 min

Now, we convert it into minutes:

t = (2 h)(60 min/1 h) + 14 min

t = 120 min + 14 min = (134 min)(60 s/1 min)

t = 8040 s

Therefore, the value of velocity will be:

v = (4.6 x 10⁵ m)/8040 s

v =  57.2 m/s

How many meters are in 5.0 cm?
500
0.050
0.0005
0.5

Answers

Explanation:

100cm=1m

5 cm= x

cross multiple

x=5/100

=0.05m

There are 0.05 meters in 5 cm. The correct option among the following is option (B).

In the metric system, a centimeter (cm) is a unit of length. It is one centimeter (1 cm = 0.01 m) in size. Small distances or measurements, such as the length, height, or width of items, are frequently measured in centimeters. Due to its practical size for many routine measurements, it is also frequently employed in scientific and mathematical computations.

In the International System of Units (SI), the meter serves as the base unit and is frequently used to measure lengths, heights, and other measurements. It serves as the basic building block for other metric units like centimeters (one meter equals one hundred centimeters) and kilometers (one kilometer equals one thousand meters).

So, to convert 5.0 cm to meters:

5.0 cm ÷ 100 = 0.05 m

Hence, 5.0 cm is equal to 0.05 meters. The correct option is (B).

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4. What is the velocity of an object that doesn't move?
It depends on the object b. it depends on the speed c. it depends on the height
O mis
help

Answers

Answer:

Acceleration /Speed

Explanation:

An objects Velocity can be determined by acceleration,

Please pay attention in your middle school class, speed and velocity quiz.

The mass of a string is 20 g and it has a length of 3.2 m. Assuming that the tension in the string is 2.5 N, what will be the wavelength of a travelling wave that is created by a sinusoidal excitation of this string with a frequency of 20 Hz. Provide the wavelength in units of m. Please note: You do not include the units in your answer. Just write in the number.

Answers

Answer:

The wavelength of the wave is 1 m

Explanation:

Given;

mass of the string, m = 20 g = 0.02 kg

length of the string, L = 3.2 m

tension on the string, T = 2.5 N

the frequency of the wave, f = 20 Hz

The velocity of the wave is given by;

[tex]v = \sqrt\frac{T}{\mu} {}[/tex]

where;

μ is mass per unit length = 0.02 kg / 3.2 m

μ = 6.25 x 10⁻³ kg/m

[tex]v = \sqrt{\frac{T}{\mu} } \\\\v = \sqrt{\frac{2.5}{6.25*10^{-3}} } \\\\v = 20 \ m/s[/tex]

The wavelength of the wave is given by;

λ = v / f

λ = (20 m/s )/ (20 Hz)

λ = 1 m

Therefore, the wavelength of the wave is 1 m

Aldis is swinging a ball tied to the end of a string over his head. Suddenly, the string breaks and the ball flies away. Arrow best represents the path the ball follows after the string breaks.

Answers

Answer:

Straight line in the direction of the tangential velocity the ball had at the moment the string broke

Explanation:

After the string breaks, the ball now disconnected from the centripetal force that was exerted via the string, continues its travel in a straight line in the direction of the tangential velocity it had at the moment the string broke.

Answer:

B

Explanation:

just took the test :)

1. Looking at the planet vs. eccentricity table, which two planets have the greatest eccentricity?

Answers

Answer:

Pluto & Mercury

Explanation:

Pluto's eccentricity is 0.248

Mercury's eccentricity is 0.206

A car travels 20 meters east
in 1.0 second and then travels
10 meters west in 20 seconds. The
displacement of the car at the end
of this 3.0-second interval is-

Answers

Answer:

Alright the other day.

The overall length of a piccolo is 30.0 cm. The resonating air column is open at both ends. (a) Find the frequency of the lowest note a piccolo can sound. (Assume that the speed of sound in air is 343 m/s.) Hz (b) Opening holes in the side of a piccolo effectively shortens the length of the resonant column. Assume the highest note a piccolo can sound is 3 000 Hz. Find the distance between adjacent antinodes for this mode of vibration.

Answers

Answer:

(a)  the frequency of the lowest note the piccolo can sound is 571.7 Hz

(b) the distance between adjacent antinodes is 5.72 cm

Explanation:

(a)

Given;

length of piccolo, L = 30 cm = 0.3 m

the speed of sound in air is 343 m/s

The wavelength of a pipe open at both ends, for the first harmonic is given;

L = A → N + N → A

L = λ / 4 +  λ / 4

L = λ / 2

λ = 2L

λ = 2 x 0.3 = 0.6 m

The fundamental frequency (lowest frequency) is given  by;

f₀ = v / λ

f₀ = (343 / 0.6)

f₀ = 571.7 Hz

(b)

Given;

highest note, f = 3000 Hz

the distance between adjacent antinodes is given by;

[tex]d = \frac{v}{2f}\\\\ d = \frac{343}{2*3000}\\\\ d = 0.0572 \ m\\\\d = 5.72 \ cm[/tex]

where do plants get the energy they need for photosynthesis
(A) leaves
(B) the sun
(C) sugars
(D) water

Answers

they get their energy from photosynthesis, so the answer would be (B) the sun

Convert 2536 mm/min to m/s. Use dimensional analysis.

Answers

Answer:

As we know that,

1 mm/min = 1.66667E-5 m/s1 m/s = 60000 mm/min

Now, come to the question -

[tex] \\ \implies \sf \: 2536 \times 1.66667E-5 m/s \\ \\ \\ \implies \sf \blue{0.0422666667 \:m/s } \\ [/tex]

Result : 2536 mm/min = 0.0422666667 m/s.

An automobile is driven on a straight road, and the distance traveled by the automobile after time t=0 is given by a quadratic function a where a(t) is measured in feet and t is measured in seconds for 0 <= t <= 12. Of the following, which gives the best estimate of the velocity of the automobile, in feet per second, at time t = 8 seconds?

a. s(8)
b. s(8)/8
c. s(12)- s(2)/ 12-2
d. s(9)- s(7)/9-7

Answers

Answer:

[tex]Velocity = \frac{s(8)}{8}[/tex]

Explanation:

Given

[tex]0 \leq t \leq 12[/tex]

Required

Determine the velocity when t = 8

This type of velocity is referred to as an instantaneous velocity.

In this case, it is calculated using

[tex]Velocity = \frac{Distance\ at\ 8 second}{t = 8}[/tex]

Given that s(t) models the distance;

s(8) = distance at 8 seconds

So;

[tex]Velocity = \frac{s(8)}{8}[/tex]

Option B answers the question

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Collective nouns are generally classified as which of the following?A. singularB. abstractC. complexD. compoundE. proper What is the prime factorization of 96? 8 12 2 2 2 2 3 25 3 25 32 If the area of a square room is 100 square meters, what is the length of one side of the room in meters? if PQ=8 and Q lies at -13 where could P be located? The______converts sound waves into electrochemical impulses which are transmitted to the brain. A cannonball made of iron has a volume of 110. cm3. What is the mass, in kilograms, of the cannonball? Please Help!! 8 Points!! Brainliest Answer!! is 6.458 a rational number name the three States of matter A pasta factory made 328.16 pounds of pasta in 7 minutes. How much pasta, on average, did the factory make each minute? What is 0.941941 repeating in fraction form ( simplest form) I need help!!!! Use the number line to find the coordinate of the midpoint of segment DE Now imagine the story is being told by a different narrator. Use the RAFT strategy to come up with different possible voices you could use to describe the same incident. 2(10 6) 2 + 3(12 10) Is the answer C or B Why didn't the butterfly go to the dance? show your thinking! Explain how you would effectively communicate instructions to a 5 year old. In a market system the allocation of scarce goods involves the consideration of:_____.a. what must be sacrificed in using a resource for its next-best use. b. identifying the possibility of professional advancement. c. the time required to pursue an economic activity. d. the dollar cost of any good or service. realizedLinnaeus's ? Select the appropriate definite article for each vocabulary word to achieve gender/number agreement. (el, la, los, las) 1. [ Select ] celular 2. [ Select ] biblioteca 3. [ Select ] destacador 4. [ Select ] cuadernos 5. [ Select ] reloj 6. [ Select ] lpiz 7. [ Select ] clases 8. [ Select ] librer