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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.

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An elevator filled with passengers has a mass of 1603 kg. (a) The elevator accelerates upward from rest at a rate of 1.20 m/s2 f
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Answer:

T = 17649.03 N = 17.65 KN

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A tensile test specimen has a gage length = 50 mm and its cross-sectional area = 100 mm2. The specimen yields at 48,000 N, and t
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strain for offset yield point

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