Above Earth

To what height must a boy be raised above the earth to see one-fifth of its surface.

Correct answer:

h =  4252 km

Step-by-step explanation:

R=6378 km S1=4π R2=4 3.1416 63782511185932.5225 km2 S=1/5 S1=1/5 511185932.5225102237186.5045 km2 S=2πRv v=S/(2π R)=102237186.5045/(2 3.1416 6378)=512756=2551.2 y=Rv=63782551.2=519134=3826.8 x=R2y2=637823826.82=525512=5102.4 k=\cotanα=x/y=(h+v)/x x/y=(h+v)/x h+v=x2/y h=x2/yv=5102.42/3826.82551.2=4252 km

Did you find an error or inaccuracy? Feel free to write us. Thank you!

Tips for related online calculators
Need help calculating sum, simplifying, or multiplying fractions? Try our fraction calculator.
The Pythagorean theorem is the base for the right triangle calculator.
See also our trigonometric triangle calculator.

We encourage you to watch this tutorial video on this math problem: video1   video2   video3

Related math problems and questions: