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The distance from the north pole to the equator is approximately 10,000km.Use this information to find and approximate value for the earth's radius
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Answer 1

Is this a question about a sphere or about a circle?

Answer 2

I think its about finding Radius and circumference of circles.

Answer 3

circle

Answer 4

no I just have to find the radius

Answer 5

Is C the centre of the circle?

Answer 6

Then you use Pythagoras to find the length of the two sides (which are the same) knowing the hypotenuse.

So

a^2 + b^2 = c^2
a = b
c = 10,000

Answer 7

Or is the length of the ARC 10000? This is not a well worded question.

Answer 8

If the arc is 10000, then you use the formula for circumference of a circle (2pi*r) to find the radius.

Answer 9

But of course if the book is talking about the Earth, then none of this applies because the Earth is an oblate spheroid.

Answer 10

I think it its its from the north pole N to the equator E

Answer 11

Well use the circumference method and the pythagoras method and see which one gives you the right answer.

Answer 12

so the circumference of a circle is 2pir what you know that is 360 degree

so what you know from the text of your exercise is that to an segment (part) with 90 degree has a circumference distance of 10000 km

but you know again that this 90 degree is 1/4 of 360
so now you can calculi using this

to 360/4 ----- 10000 km
than to 360 ----- x
-----------------------------

x = 360*10000 /(360/4) = 360*10000 * 4/360 =4*10000 =40000 km

than now you know that the circumference of the Earth is 40000 km what is equale
2pir = 2*3,14*r
so using this you will can easy calculi the radius

2pir=2*3,14*r = 6,28*r

6,28*r=40000

r= 40000/6,28 = 6369,4

so what mean that the radius of the earth is aproximatly 6370 km