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
kolezko [41]
3 years ago
9

Calculate the rate of heat conduction through a layer of still air that is 1 mm thick, with an area of 1 m, for a temperature of

20C
Physics
2 answers:
max2010maxim [7]3 years ago
6 0

Answer:

The rate of heat conduction through the layer of still air is 517.4 W

Explanation:

Given:

Thickness of the still air layer (L) = 1 mm

Area of the still air = 1 m

Temperature of the still air ( T) = 20°C

Thermal conductivity of still air (K) at 20°C = 25.87mW/mK

Rate of heat conduction (Q) = ?

To determine the rate of heat conduction through the still air, we apply the formula below.

Q =\frac{KA(\delta T)}{L}

Q =\frac{25.87*1*20}{1}

Q = 517.4 W

Therefore, the rate of heat conduction through the layer of still air is 517.4 W

Goryan [66]3 years ago
3 0

Answer: Rate of heat transfer q = 517.4W

Explanation:

Thermal conductivity is a material property that describes its ability to conduct heat. Thermal conductivity is the quantity of heat transmitted through a unit thickness of a material, in a direction normal to a surface of unit area,due to a unit temperature gradient under steady state conditions. It can be shown mathematically using the equation below;

Q/t = kA(∆T)/d

q = kA(∆T)/d

q = Q/t = rate of heat transfer

Q = total amount of heat transfer

t = time

k = thermal conductivity of material

A = Area

d= distance

For the case above, the material used is still air.

k for still air at 20°C and 1bara = 0.02587W/mK

A = 1m^2

d = 1mm = 0.001m

∆T = 20°C = 20K

q = 0.02587×1×20/0.001

q = 517.4W

Therefore, the rate of heat conduction through the still air is 517.4W

You might be interested in
Which graph shows acceleration? A graph of position (meters) versus time (seconds) has a straight line running from 0 seconds 0
charle [14.2K]

It's the one that has a concave line running upward.

6 0
2 years ago
Read 2 more answers
Microwave ovens use microwave radiation to heat food. the microwaves are absorbed by the water molecules in the food, which is t
PIT_PIT [208]
<span>step 1: energy required to heat coffee E = m Cp dT E = energy to heat coffee m = mass coffee = 225 mL x (0.997 g / mL) = 224g Cp = heat capacity of coffee = 4.184 J / gK dT = change in temp of coffee = 62.0 - 25.0 C = 37.0 C E = (224 g) x (4.184 J / gK) x (37.0 C) = 3.46x10^4 J step2: find energy of a single photon of the radiation E = hc / λ E = energy of the photon h = planck's constant = 6.626x10^-34 J s c = speed of light = 3.00x10^8 m/s λ = wavelength = 11.2 cm = 11.2 cm x (1m / 100 cm) = 0.112 m E = (6.626x10^-34 J s) x (3.00x10^8 m/s) / (0.112 m) = 1.77x10^-16 J step3: Number of photons 3.46x10^4 J x ( 1 photon / 1.77x10^-16 J) = 1.95x10^20 photons</span>
7 0
3 years ago
Read 2 more answers
What is the advantage of constantly performing endurance training such as Brisk walking or jogging, Yard work, Dancing, Swimming
Eduardwww [97]
Exercise or Getting grader Stomata
5 0
2 years ago
Define neuron and nerve<br>cell​
san4es73 [151]

Answer: Hi!

A neuron is a basic working unit of the brain. Neurons are special cells designed to transfer information to other nerve, muscle, or gland cells. They are pretty cool - looking too! (A slightly irregular circular shape with branches reaching out from all sides.) A neuron is a nerve cell. Nerve cells are the way of communication in the nervous system.

Hope this helps!

3 0
3 years ago
Read 2 more answers
What is the main reason water from the ocean turns to water vapor , and then evaporates into the air
melamori03 [73]

Hello! :)

C) heat from the sun

Why?

Because the sun’s heat makes the water turn to steam—or what we call “water vapor.”

Hope this helped and I hope I answered in time!

Good luck!

~ Destiny ^_^

3 0
2 years ago
Read 2 more answers
Other questions:
  • The velocity of a car is 65 m/s and it’s mass is 2515 kg. What is it’s KE?
    10·2 answers
  • Which example best illustrates the transfer of energy between two waves?
    5·2 answers
  • An astronaut on an alien planet drops a rock into a crater which is 100 meters deep. The rock hits the bottom of the crater 4 se
    8·1 answer
  • A Honda Civic and an 18 wheeler approach a right angle intersection and then collide. After the collision, they become interlock
    10·1 answer
  • What is the mass of a cart that accelerates at 3.0 m/s if a 0.5 N force is applied?
    6·1 answer
  • What is the kinetic energy of a 1.0-kg billard ball that moves at 5.0 m/s?
    9·1 answer
  • The matter that makes up a planet is distributed uniformly so that the planet has a fixed, uniform density. How does the magnitu
    5·1 answer
  • Suppose a rocket ship accelerates upwards with acceleration equal in magnitude to twice the magnitude of g (we say that the rock
    9·1 answer
  • What is a solenoid
    6·2 answers
  • PLEASE ANSWER 50 points
    12·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!