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A mobile base station (BS) in an urban environment has a power measurement of 25 µW at 425 m. If the propagation follows an inverse cube-power law (Section 3.2.2), what is a reasonable power value, in µW, to assume 1.7 km from the BS?

Give your answer in scientific notation to two decimal places.
Original post by flubbsy1990
A mobile base station (BS) in an urban environment has a power measurement of 25 µW at 425 m. If the propagation follows an inverse cube-power law (Section 3.2.2), what is a reasonable power value, in µW, to assume 1.7 km from the BS?

Give your answer in scientific notation to two decimal places.


Power is proportional to 1 / (length)^3, so basically the length^(-1/3).

1700 is 4 times bigger than 425, so…
Original post by flubbsy1990
A mobile base station (BS) in an urban environment has a power measurement of 25 µW at 425 m. If the propagation follows an inverse cube-power law (Section 3.2.2), what is a reasonable power value, in µW, to assume 1.7 km from the BS?

Give your answer in scientific notation to two decimal places.

What are you stuck on?

if you say x = 1700/425

you'd want 1/x3 times the power given at 425m
Im stuck on. scientific notation to two decimal places.
Original post by flubbsy1990
Im stuck on. scientific notation to two decimal places.


Oh yeah, well I think that it probably wants you to give an answer in Watts using scientific notation with one digit on the left of the decimal point and the mantissa rounded to 2 digits

so if it was 0.012321 μW
you'd put 1.23 *10-8 W

...but I think it would have been more sensible for the question to ask for significant figures really.
did anyone get the answer to this? my head has fallen off ha
So has anyone had the answer to this? my head has totally fallen off .

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