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
Andrew [12]
3 years ago
12

You have a tungsten sphere (emissivity ε = 0.35) of radius 25 cm at a temperature of 25°C. If the sphere is enclosed in a room w

hose walls are kept at -5°C, what is the net flow rate of energy out of the sphere?
Physics
1 answer:
egoroff_w [7]3 years ago
8 0

Answer:

Explanation:

Stefan's formula for emission of radiation is

E = e σ A  ( T⁴ - T₀⁴ )

E is energy radiated , e is emissivity , σ is stefan's constant , T is temperature of object and T₀ is temperature of surrounding. A is area of surface .

E = .35 x 5.67 x 10⁻⁸ ( 298⁴ - 268⁴ ) x 4π x .25²

= 1.9845 x 10⁻⁸ ( 78.86 - 51.58 ) x 10⁸ x .0625

= 3.38  J /s

You might be interested in
explain which properties of metals make sterling silver the best material for you to create hammered earrings.
7nadin3 [17]

It is malleable

Explanation:

The property that makes metals such as sterling silver the best to create hammered earrings is their malleability.

All metals have a unique and fascinating property of being malleable. They can be carved into any of shape. When hammered they simply draw out and retain their long range ordering of their crystal lattice.

This is made possible by the presence of metallic bonding between the atoms.

  • The bulk of the physical properties of metals can be attributed the metallic bonds in them.
  • Metals have large sea of electrons in them.
  • In forming metallic bonds, there is an attraction between the positive nuclei of all the closely packed atoms in the lattice and the electron cloud jointly formed by all the atoms by loosing their outermost shell electrons.
  • Metals like silver have low ionization energy.
  • When they are hammered, they spread out the energy from the hammering.

learn more:

Metals brainly.com/question/2474874

#learnwithBrainly

8 0
3 years ago
Light waves
irga5000 [103]

Answer:

a

Explanation:

Because I searched it up

7 0
3 years ago
Read 2 more answers
Long Jump: inital center of mass height of 1.08 m, final center of mass height of 0.42 m, projection velocity of 8.7 m/s, projec
sammy [17]

Answer:

1) The maximum jump height is reached at A. 0.337s

2) The maximum center of mass height off of the ground is B. 1.64m

3) The time of flight is C. 0.834s

4) The distance of jump is B. 7.49m

Explanation:

First of all we need to decompose velocity in its rectangular components, so

v_{xi}=8.7m/s(cos 22.3\°)=8.05m/s= constant\\v_{yi}=8.7m/s(sin 22.3\°)=3.3m/s

1) We use, v_{fy}=v_{iy}-gt, as we clear it for t and using the fact that v_{fy}=0 at max height, we obtain t=\frac{v_{iy}}{g} =\frac{3.3m/s}{9,8m/s^{2}} =0.337s

2) We can use the formula y_{max}=y_{i}+v_{iy}t-\frac{gt^{2}}{2} for t=0.337s, so

y_{max}=1.08m+(3.3m/s)(0.337s)-\frac{(9.8m/s^{2})(0.337)^{2}}{2}=1.64m

3) We can use the formula y_{f}=y_{i}+v_{iy}t-\frac{gt^{2}}{2}, to find total time of fligth, so 0.42=1.08+3.3t-\frac{(9.8)t^{2}}{2}\\0=-4.9t^{2}+3.3t+0.66, as it is a second-grade polynomial, we find that its positive root is t=0.834s

4) Finally, we use x=v_{x}t=8.05m/s(0.834s)=6.71m, as it has an additional displacement of 0.77m due the leg extension we obtain,

x=6.71m+0.77m=7.48m, aprox x=7.49m

5 0
4 years ago
A box has a mass of 5.8kg. The box is lifted from the garage floor and placed on a shelf 2.5m off the ground. How much gravitati
Damm [24]
Gravitational potential energy  = 

                        (mass)  x  (gravity)  x  (height)

                =    (5.8 kg)  x  (9.8 m/s²)  x  (2.5 m)

                =           142.1 Joules         (C)
5 0
3 years ago
The left side of the lever was forced down 10 inches in order to raise the rock 7 inches. The ideal mechanical advantage is
Yanka [14]

Answer:

1.42

Explanation:

<em> got it right on my homework </em>

6 0
3 years ago
Other questions:
  • The direction of rotation of Venus is _________ to the direction of all other planets.
    9·1 answer
  • assuming that there are no outside forces, what will happen if two neutral atoms are placed 1 M apart in a vacuum. a)the atoms w
    13·1 answer
  • A penny is placed at the outer edge of a disk (radius = 0.179 m) that rotates about an axis perpendicular to the plane of the di
    15·1 answer
  • Our resources can only supply a small fraction of our wants. true false
    5·1 answer
  • A Formula One race car with mass 770.0 kg is speeding through a course in Monaco and enters a circular turn at 235.0 km/h in the
    6·1 answer
  • The displacement (in meters) of an object moving in a straight line is given by s=1+2t+1/4t^2^2, where t is measured in seconds.
    10·1 answer
  • A batter hits a foul ball. The 0.14-kg baseball that was approaching him at 40 m/s leaves the bat at 30 m/s in a direction perpe
    15·2 answers
  • A polythene rod may be charged by rubbing it with a cloth while being held in the hand but a metal rod cannot be charged in a si
    14·1 answer
  • El sistema energético que importancia tiene en el cuerpo
    10·1 answer
  • Given the velocity v= ds dt and the initial position of a body moving along a coordinate line, find the body's position at time
    8·2 answers
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!