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
Nimfa-mama [501]
3 years ago
15

A python can detect thermal radiation from objects that differ in temperature from their environment as long as the received int

ensity of thermal radiation is greater than 0.60 W/m². Your body emits a good deal of thermal radiation; a typical human body has a surface area of 1.8 m², a surface temperature of 30°C, and an emissivity e = 0.97 at infrared wavelengths. As we've seen, the intensity of a source of radiation decreases with the distance from the source.
If you are outside on a cool, dark night, what is the maximum distance from which a python could detect your presence?
Physics
1 answer:
yanalaym [24]3 years ago
3 0

Answer:

10.52 m

Explanation:

The power radiated by a body is given by

P = σεAT⁴ where ε = emissivity = 0.97, T = temperature = 30 C + 273 = 303 K, A = surface area of human body = 1.8 m², σ = 5.67 × 10⁻⁴ W/m²K⁴

P = σεAT⁴ = 5.67 × 10⁻⁸ W/m²K⁴ ×  0.97 × 1.8 m² × (303)⁴ = 834.45 W

This is the power radiated by the human body.

The intensity I = P/A where A = 4πr² where r = distance from human body.

I = P/4πr²

r = (√P/πI)/2

If the python is able to detect an intensity of 0.60 W/m², with a power of 834.45 W emitted by the human body, the maximum distance r, is thus

r = (√P/πI)/2 = (√834.45/0.60π)/2 = 21.04/2 = 10.52 m

So, the maximum distance at which a python could detect your presence is 10.52 m.

You might be interested in
What is the net force on a bathroom scale when a 110 pound person stands on it? How do you know?
USPshnik [31]
The scale is a rest scale reads the support for is not enough net force.
8 0
2 years ago
An object accelerates from rest and travels 53 m west in 5.2 s. Determine the acceleration
zmey [24]

Answer:

20.4m/s²

Explanation:

Given parameters:

Initial velocity  = 0m/s

Distance  = 53m

Time  = 5.2s

Unknown:

Acceleration  = ?

Solution:

This is a linear motion and we use the right motion equation;

        S = ut  + \frac{1}{2}at²

S is the distance

u is the initial velocity

a is the acceleration

t is the time

 Insert the parameters and solve;

       53  = (0x 5.2) +  \frac{1}{2} x a x 5.2

       53  = 2.6a

         a = \frac{53}{2.6}  = 20.4m/s²

6 0
3 years ago
I need homework help
KIM [24]
1) the weight of an object at Earth's surface is given by F=mg, where m is the mass of the object and g=9.81 m/s^2 is the gravitational acceleration at Earth's surface. The book in this problem has a mass of m=2.2 kg, therefore its weight is 
F=mg=(2.2 kg)(9.81 m/s^2)=21.6 N

2) On Mars, the value of the gravitational acceleration is different:g=3.7 m/s^2. The formula to calculate the weight of the object on Mars is still the same, but we have to use this value of g instead of the one on Earth: F=mg=(2.2 kg)(3.7 m/s^2)=8.1 N

3) The weight of the textbook on Venus is F=19.6 N. We already know its mass (m=2.2 kg), therefore by re-arranging the usual equation F=mg, we can find the value of the gravitational acceleration g on Venus: 
g= \frac{F}{m}= \frac{ 19.6 N}{2.2 kg}=8.9 m/s^2

4) The mass of the pair of running shoes is m=0.5 kg. Their weight is F=11.55 N, therefore we can find the value of the gravitational acceleration g on Jupiter by re-arranging the usual equation F=mg: 
g= \frac{F}{m} = \frac{11.55 N}{0.5 kg} =23.1 m/s^2

5) The weight of the pair of shoes of m=0.5 kg on Pluto is F=0.3 N. As in the previous step, we can calculate the strength of the gravity g on Pluto as 
g= \frac{F}{m} = \frac{0.3 N}{0.5 kg} =0.6 m/s^2

<span>6) On Earth, the gravity acceleration is </span>g=9.81 m/s^2<span>. The mass of the pair of shoes is m=0.5 kg, therefore their weight on Earth is 
</span>F=mg=(0.5 kg)(9.81 m/s^2)=4.9 N<span>
</span>
5 0
3 years ago
Red light from three separate sources passes through a diffraction grating with 5.60×105 slits/m. The wavelengths of the three l
shtirl [24]

Answer:

I can help

Explanation:

6 0
3 years ago
an empty propane tank dropped from a hot air balloon hits the ground with a speed of 143.8 m/s. from what height was the tank re
vodomira [7]
What you know:
Vi=0m/s
Vf=143.8m/s
A=-9.8m/s
d=???
Use the equation Vf^2=Vi^2+2A(d)
Rearrange to isolate d: d=Vf^2/2A
d=(143.8)^2/2(-9.8)
d=20678.4/-19.6
d=-1055m
The tank was released from a height of 1055m
8 0
3 years ago
Other questions:
  • PLEASE HELP IM STUCK ON THIS I STUDIED AND I STILL DONT GET IT I ASKED TEACHERS BUT THEY WONT HELP PLZ HELP
    14·1 answer
  • Phenotype describes
    14·1 answer
  • Which of these is part of the middle ear? A. External auditory meatus B. Tympanic membrane C. organ of corti D. The ossicles
    6·2 answers
  • You are driving home from school steadily at for 180 km. It then begins to rain and you slow to You arrive home after driving 4.
    13·1 answer
  • What is the definition of conservation of energy
    5·2 answers
  • What is the definition of power​
    11·1 answer
  • What is the equation used to calculate power?
    15·2 answers
  • Which of the following refers to the distance between the successive compression and rarefaction?
    12·1 answer
  • In which medium does light travel faster: one with a critical angle of 27.0° or one with a critical angle of 32.0°? Explain. (Fo
    8·1 answer
  • Will give you brainliest pls help
    14·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!