Test your knowledge of the earth
A rope is tied snugly around the earth's equator.It was taken out so that an extra metre can be added in.When you place this extended rope back to the equator,a gap will form.Find the magnitude of this gap,in centimetres,rounded to the nearest whole number
The answer is 16.
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2 solutions
2 π ( r 2 ) = 2 π ( r 1 ) + 1
r 2 − r 1 = 2 π 1 m e t e r s
r 2 − r 1 = 2 π 1 × 1 0 0 c e n t i m e t e r s
r 2 − r 1 = 1 6
Let the circumference of the Earth C = 2 • pi • r If we add 1 to this: C = 2 • pi • r + 1 The magnitude is the radius, the distance from the center, So to find the new radius from this equation, we find C/(2 • pi) Which is (2 • pi • r) / (2 • pi) + 1 / (2 • pi) Which gives r + 1 / (2 • pi). Since r is our previous radius, the added magnitude is equal to 1 / (2•pi) or about 0.159 meters. In nearest centimeter, this is 16.