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
Mila [183]
3 years ago
12

What is the net power that a person with surface area of 1.20 m2 radiates if his emissivity is 0.895, his skin temperature is 27

°C, and he is in a room that is at a temperature of 17°C m2 radiates if his emissivity is 0.895, his skin temperature is 27°C, and he is in a room that is at a temperature of 17°C. (σ = 5.67 × 10-8 W/m2 ∙ K4)

Physics
1 answer:
marissa [1.9K]3 years ago
4 0

Explanation:

Below is an attachment containing the solution.

You might be interested in
Two charged objects have a repulsive force of 0.040 N. If the distance separating the objects is doubled, then what is the new f
Georgia [21]

Answer:

Two charged objects have a repulsive force of 0.080 N. If the charge of both of the objects is doubled, then what is the new force? Explanation: Electrostatic force is directly related to the charge of each object. So if the charge of both objects is doubled, then the force will become four times greater.

Explanation:

hope this helps

7 0
2 years ago
Which of the following is NOT a function of the lens in the eye?
tatyana61 [14]

Answer:

it is a light receptor that generates nerve signals that are sent to the brain

Explanation:

the lens are like the glasses, this means that is used to see things better. You just put them in your eye and that's all it's not connected to the brain

8 0
2 years ago
B. If we drop a ball from the roof, its falls<br>downward​
frosja888 [35]

Answer:

yes ,what's the question

and if the question is why

then it's for gravity

4 0
2 years ago
Read 2 more answers
A woman can row a boat at 5.60 km/h in still water. (a) If she is crossing a river where the current is 2.80 km/h, in what direc
katrin2010 [14]

Answer:

a) θ=210°, b) t=1.155hr, c) t=1.333hr, d) t=1.333hr, e) θ=180° (straight across), f) t=1hr.

Explanation:

So, the very first thing we nee to do when solving this problem is draw a diagram that represents it. In the attached picture I show a diagram for each part of this problem.

part a)

So, for her to move in a direction directly opposite her starting point, the x-component of her velocity must be de same as the velocity of the river in the opposite direction. We can use this fact to find the angle we need. If we analize the triangle I drew in the diagram, we can ses that:

cos \theta = \frac {V_{river}}{V_{boat}}

When solving for theta, we get that:

\theta =cos^{-1} ( \frac {V_{river}}{V_{boat}})

so now we can substitute the corresponding values:

\theta =cos^{-1} ( \frac {2.80km/hr}{5.60km/hr}})

Which yields:

\theta = 60^{o}

but we are measuring the angle relative to the line perpendicular to the river, positive if down the river. So we need to subtract the angle from 270° so we get:

θ=270°-60°=210°

part b)

for part b, we need to find what the y-component for the velocity of the boat is for an angle of 210° as shown in the problem, so we get that:

V_{y}=5.60km/hr*cos(210^{o})

V_{y}=-4.85km/hr

The woman will head in a negative 5.60km distance from one side to the other, so we get that the time it takes her to go to the other side of the river is:

t=\frac{y}{V_{y}}

t=\frac{5.60km}{4.85km/hr}=1.155hr

part c)

In order to find the time it takes her to travel 2.80km down and up the river, we need to find the velocities she will have in both directions. First, down stream:

V_{ds}=V_{river}+V{boat}

V_{ds}=2.80km/hr+5.60km/hr=8.40km/hr

and now up stream:

V_{us}=V_{boat}-V{river}

V_{us}=5.60km/hr-2.80km/hr=2.80km/hr

Once we got these two velocities we will now need to find the time to take each trip:

time down stream:

t_{ds}=\frac{x}{v_{ds}}

t_{ds}=\frac{2.80km}{8.40km/hr}=0.333hr

and the time up stream:

t_{us}=\frac{x}{v_{us}}

t_{us}=\frac{2.80km}{2,80km/hr}=1hr

so the total time will be:

t_{ds}+t_{us}=0.333hr+1hr=1.333hr

d) the time it takes the boat to go upstream and then downstream for the same distance is the same as the time we got on part c, since both times will be the same but they will come in different order, but their sum will be just the same:

t=1.333hr

e) For her to cross the river faster, she must row in a 180° direction (this is in a direction straight accross the river) that way she will use all her velocity to move across the river. (Even though she will move a certain distance horizontally and will not reach a point opposite to the starting point.)

f) In order to find the time it takes her to get to the other side, we need to divide the distance into the velocity of the boat.

t=\frac{d}{v_{boat}}

t=\frac{5.60km}{5.60km/hr}

so

t= 1hr

4 0
3 years ago
Read 2 more answers
What is the period of a soundwave whose wavelength is 20.0 m? Use values from the book and show ALL of your work.
Liono4ka [1.6K]
<h3><u>Answer;</u></h3>

Period = 1/17 seconds

<h3><u>Explanation;</u></h3>
  • Wavelength is related to period by the expression:

<em>speed = wavelength / period </em>

  • If we are given the speed, then we can easily calculate the period at the wavelength of 20 m.

<em>Given the speed of sound wave as 340 m/s </em>

<em>Period = Wavelength/ speed</em>

<em>            = 20 m/340 m/s</em>

<em>            </em><u><em>= 1/17 seconds</em></u>

7 0
2 years ago
Other questions:
  • Planet with a density so low that it could float on water
    14·1 answer
  • Electromagnets in radios can be used to A) play a CD. B) create sound. C) change the station. D) make a remote control.
    13·2 answers
  • What is the resistance of a 4.4-m length of copper wire 1.5 mm in diameter? The resistivity of copper is 1.68×10−8Ω⋅m.
    14·1 answer
  • What is the magnitude of the magnetic field created 4.0m away from a 10.0 A current?
    14·1 answer
  • A 2.0-kg ball with an initial velocity of (4i + 3j) m/s collides with a wall and rebounds with a velocity of (–4i + 3j) m/s. Wha
    14·1 answer
  • Andy has two samples of liquids. Sample A has a pH of 4, and sample B has a pH of 6. What can Andy conclude about these two samp
    8·1 answer
  • Why does a revolving stone tied in a string flies away when the string breaks??
    8·1 answer
  • How do I get number of atoms?
    5·1 answer
  • Write a summary paragraph discussing this experiment and the results. Use the following questions and topics to help guide the c
    5·1 answer
  • Two rods of mass m, length L are stuck together to form an X shape and spun around the center. What is the rotational inertia
    11·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!