Answer:
The reasonable value = 2.96 × 10^(-1) µW
Step-by-step explanation:
* Lets explain how to solve the problem
- A mobile base station in an urban environment has a power
measurement of 8 µW at 225 m
- The propagation follows an inverse cube power law
- We need to find the reasonable value to assume at a distance
678 m from the base station
∵ The propagation follows an inverse cube power law
- <em>The power would have been decreased by a factor 1/n³ </em>
<em> times the power as a distance increasing</em>
∵ n = the ratio between the distances
∵ The distance are 675 m and 225
∴ n = 675/225 = 3
∴ 1/n³ = 1/3³ = 1/27
- The reasonable value is the product of the power measurement of
8 µW and 1/27
∴ The reasonable value = 8 × 1/27 = 8/27 µW = 0.296296
∴ The reasonable value = 2.96 × 10^(-1) µW
Draw or sketch out any problems like this, otherwise they appear abstract.
A circle’s area can be calculated by (pi d^2)/4 We have an area of 56 cm (^2?), so
pi d^2 = 56 x 4 (or 224) d^2 = 224/pi, d = √(224/pi)
A circle circumscribed around a square has a diameter equivalent to the length of the square’s diagonal, so the square’s diagonal is √(224/pi) (same as the circle diameter…)
A square’s side can be calculated, knowing its diagonal length, by use of Pythagoras’ theorem… The diagonal √(224/pi) is squared, divided by two, since the square’s sides are all equal, and the resulting number’s square root is calculated.
Squaring √(224/pi), we get 224/pi, and dividing by two, we get 112/pi, which is 35.6507 (cm^2), and the square root is 5.9708 cm, the side of the square.
I cannot emphasize enough that a drawing or sketch is an invaluable tool for these tasks, it saves having to retain a “picture” in your head. Note that a calculator was not required up until the last moment, dividing 112 by pi, and finding the square root of that answer. Picking up the calculator too early obliges you to transcribe numbers from the calculator to paper, and that can lead to issues. Try to enjoy maths, see it as a challenge not a chore. (and use correct units!)
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Related Questions (More Answers Below)
Okay follow these patterns and you will always get your answer
Cone = (13)πr2h, where r is the radius and h is the height.
Cube = s2, where s is the length of the side.
Cylinder = πr2h, where r is the radius and h is the height.
Rectangular prism= l×w×h, where l is the length, w is the width and h is the height.
Sphere = (43)πr3, where r is the radius.
ANSWER: (D) 904.78 cm^3
Answer:
x is equal to positive 5/6 and negative 5/6
Step-by-step explanation:
To solve this, you simply need to take the square root of both sides:
