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
Brut [27]
2 years ago
13

Determinar el flujo de calor a través del piso de losa cuyas medidas 3 X 5 cm y temperaturas superficiales son -20 ºC y 40 ºC, l

a conductividad térmica del material es de 1,6 X 10 -3 cal/cm s ºC y su espesor es de 10 cm durante 1 hora.
Una aluminio de 12 cm de grosor, pero están perfectamente aislados en las demás paredes. Cada cuarto es un cubo de 4,0 m de arista. Si el aire de uno de los cuartos está a 10 ºC y el otro a 30 ºC. ¿Cuántos calor se conduce durante dos minutos? 1,7X 10 -4 cal/ cm s ºC
Una pared de asbesto de 0,15 cm de espesor 1400°C y 1150 ºC en las superficies interna y externa, respectivamente. ¿Cuál es la perdida de calor a través de una pared que tiene 0,5 m por 3 m de lado, en un tiempo de minuto y medio?
!!!!!!NESECITO AYUDA¡¡¡¡¡
Physics
1 answer:
sweet-ann [11.9K]2 years ago
3 0

Answer:

0,0560 cal / gºC.

You might be interested in
A firefighter with a weight of 707 N slides down a vertical pole with an acceleration of 2.79 m/s2, directed downward. (a) What
DedPeter [7]

Answer:

The vertical force acting on the firefighter = 908.27 N

Explanation:

Force: Force of a body is defined as the product of mass and its acceleration. The S.I unit of force is Newton (N)

The vertical force acting on the firefighter = Force due to the weight of the firefighter + force due to acceleration.

Ft = Fw - Fa

Where Ft = The vertical force acting on the firefighter, Fw = Force due to the weight of the firefighter, Fa = force due to acceleration.

Fw = mg

Making m the subject of formula in the equation above

m = Fw/g................... Equation 1

Where m = mass of the firefighter, g = acceleration due to gravity,

<em>Given: Fw = 707 N, </em>

<em> Constant: g = 9.8 m/s²</em>

Substituting these values into eqaution 1

m = 707/9.8

m = 72.14 kg.

But, Fa = ma

Where a = acceleration of the firefighter.

<em>Given: a = 2.79 m/s², </em>

<em>And m = 72.14 kg</em>

Fa = 72.14 × 2.79

Fa = 201.27 N

Therefore, Ft = 707 + 201.27  = 908.27 N

Ft = 908.27 N

The vertical force acting on the firefighter = 908.27 N

7 0
3 years ago
Which is not true about the pH scale?
pochemuha

Answer:

The pH scale was invented by Svante Arrhenius is false.

Explanation :

because the pH scale was invented by Soren Sorensen

4 0
3 years ago
Read 2 more answers
The head of a grass string trimmer has 100 g of cord wound in a light, cylindrical spool with inside diameter 3.00 cm and outsid
faust18 [17]

Answer:

a).11.546J

b).2.957kW

Explanation:

Using Inertia and tangential velocity

a).

w=2250*2\pi *\frac{1}{60}\\ w=235.61

I=\frac{1}{2}*m*((\frac{d_{i} }{2})^{2} +(\frac{d_{e} }{2})^{2})\\m=100g *\frac{ikg}{1000g}=0.1kg\\ d_{i}=3cm*\frac{1m}{100cm}=0.03m \\ d_{e}=18cm*\frac{1m}{100cm}=0.18m\\I=\frac{1}{2}*0.1kg*((\frac{0.03m}{2})^{2} +(\frac{0.18m}{2})^{2})\\I=0.41625x10^{-3}kg*m^{2}

Now using Inertia an w

E=\frac{1}{2}*I*(w)^{2} \\ E=\frac{1}{2}*0.416x10^{-3}*(235.61)^{2} \\E=11.54J

average power=\frac{11.4J}{0.230s}=50.2 W

b).

power=t*w

P=11.5465*0.25*235.61

P=2.957 kW

4 0
3 years ago
Read 2 more answers
What is a nebula? <br> please help I am clueless
Rainbow [258]
A nebula is gas, dust, and other things that form and form some sort of clould like thing. It also looks cool because of the colors it produces. I'm sure you could do a web search to find more about it, I don't take astronomy hahaha
4 0
3 years ago
From laboratory measurements, we know that a particular spectral line formed by hydrogen appears at a wavelength of 121.6 nanome
lina2011 [118]

Answer:

b) The star is moving away from us.

Explanation:

If an object moves toward us, the light waves it emits are compressed - the wavelength of the light will be shorter, making the light bluer. On the other hand, if an object moves away from us, the light waves are stretched, making it redder. If from laboratory measurements we know that a specific hydrogen spectral line appears at the wavelength of 121.6 nanometers (nm) and the spectrum of a particular star shows the same hydrogen line appearing at the wavelength of 121.8 nm, we can conclude that the star is moving away from npos, since the wavelength related to that star is more expanded.

7 0
3 years ago
Other questions:
  • The air in a cool region underneath cloud cover will have _____ a region with no cloud cover.
    8·2 answers
  • While hiking in the mountains, tanya observed a narrow and steep valley with a stream at the bottom of it. what most likely caus
    15·2 answers
  • A proton is located at the point (x = 1.0 nm, y = 0.0 nm) and an electron is located at the point (x = 0.0 nm, y = 4.0 nm). Find
    14·1 answer
  • In solving for the magnitude of the electric field E⃗(z) produced by a sheet charge with charge density σ, use the planar symmet
    10·1 answer
  • If a vector that is 3 cm long represents 30 km/h what velocity does a 5cm long vector which is drawn using the same scale
    11·1 answer
  • What variable(s) determine the amount of potential energy an object has?
    13·1 answer
  • Need help pls and explain also
    9·1 answer
  • A 5kg box slides across the floor with an initial velocity of 5m/s. If the coefficient of kinetic friction between the box and t
    12·1 answer
  • When does the net flux of dissolved molecules stop
    14·1 answer
  • 3 A rocket of mass 1200 kg is travelling at 2000 m/s. It fires its engine for 1 minute. The forward thrust provided by the rocke
    8·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!