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
Norma-Jean [14]
3 years ago
11

A 71 kW radio station broadcasts its signal uniformly in all directions. - What is the average intensity of its signal at a dist

ance of 220 m from the antenna? -What is the average intensity of its signal at a distance of 2200 m from the antenna?
Physics
1 answer:
marshall27 [118]3 years ago
3 0

Answer:

Explanation:

Energy of signal being radiated per second on all sides = 71 x 10³ J .

At a distance of 220 m it is spread over an area of 4 π x (220)² because it is spreading uniformly on all sides.

So energy crossing per unit area

= \frac{71\times10^3}{4 \times \pi\times(220)^2}

= 11.67 x 10⁻² Wm⁻²s⁻¹.

This is the intensity of the signal.

At 2200 m this intensity will further reduce by 100 times

So there it becomes equal to

11.67 x 10⁻⁴ Wm⁻² s⁻¹.

You might be interested in
A runaway railroad car, with mass 30x10^4 kg, coasts across a level track at 2.0 m/s when it collides with a spring loaded bumpe
Natalija [7]

Answer:

0.775 m

Explanation:

As the car collides with the bumper, all the kinetic energy of the car (K) is converted into elastic potential energy of the bumper (U):

U=K\\frac{1}{2}kx^2 = \frac{1}{2}mv^2

where we have

k=2\cdot 10^6 N/m is the spring constant of the bumper

x is the maximum compression of the bumper

m=30\cdot 10^4 kg is the mass of the car

v=2.0 m/s is the speed of the car

Solving for x, we find the maximum compression of the spring:

x=\sqrt{\frac{mv^2}{k}}=\sqrt{\frac{(30\cdot 10^4 kg)(2.0 m/s)^2}{2\cdot 10^6 N/m}}=0.775 m

8 0
3 years ago
Read 2 more answers
Design a solution that can monitor and minimize the melting of sea ice caused by human activity
dedylja [7]

Answer:

CO2 emissions from fossil fuel burning should be minimized at all cost. The CO2 are gotten when the carbons from hydrocarbons react with air(oxygen). This gas erodes the ozone layer which makes the melting of ice caps faster due to increased amount of heat radiations on the earth. This is the only best and permanent solution to the reduction of the amount of heat rays on the earth which is a global problem.

Objects which reflects back the sunrays could also be inserted into the sea to prevent the melting of the ice caps.

7 0
3 years ago
Which of the following statements best describes ergonomics?
emmainna [20.7K]
Can you provide the multiple choices​ ?
3 0
3 years ago
Read 2 more answers
A system of ideal gas at 22°C undergoes an ischoric process with an internal energy decrease of 4.30 × 10 3 4.30×103 J to a fina
Komok [63]

Answer:

The approximate change in entropy is -14.72 J/K.

Explanation:

Given that,

Temperature = 22°C

Internal energy U=4.30\times10^{3}\ J

Final temperature = 16°C

We need to calculate the approximate change in entropy

Using formula of the entropy

\Delta S=\dfrac{\Delta U}{T}

Where, \Delta U = internal energy

T = average temperature

Put the value in to the formula

\Delta S=\dfrac{-4.30\times10^{3}}{\dfrac{22+273+16+273}{2}}

\Delta S=-14.72\ J/K

Hence, The approximate change in entropy is -14.72 J/K.

5 0
3 years ago
Which statement about the horizontal distance covered by a projectile launched at an angle less than 90° is true?
mylen [45]
<h2>Answer: A</h2>

Explanation because the distance covered is equal time intervals is the same or equal.

5 0
3 years ago
Read 2 more answers
Other questions:
  • A circular wire loop has a radius of 7.50 cm. a sinusoidal electromagnetic plane wave traveling in air passes throughthe loop, w
    7·2 answers
  • Explain what cell theory is. Describe the history behind cell theory and the
    10·1 answer
  • How are the three lines of defense the same
    12·2 answers
  • The charge of an electronic is A.-2 B.-1 C.0 D.+1
    7·1 answer
  • What is a middle c site
    9·1 answer
  • I want to take a picture of the question and get the answer
    15·1 answer
  • Explain the process of <br>anomalous expansion of water​
    12·1 answer
  • Drag each tile to the correct box a chemical reaction takes place in which energy is released arrange the reactions characterist
    8·1 answer
  • Name at least two other viruses that are at all time lows due to vaccines.
    5·1 answer
  • a uniform beam of length l and mass mb is supported by two pillars located l/3 from either end, as shown in the figure. a duck o
    15·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!