0.1 cm deep scratch was made in the surface of a globe with a diameter of 40cm. Calculate the actual depth of the surface feature (represented by the scratch) on the real Earth.
2007-10-18 11:39:59 · 3 answers · asked by Anonymous in Science & Mathematics ➔ Earth Sciences & Geology
um i think u find the surface area, then times that by .1
2007-10-18 11:44:15 · answer #1 · answered by garglesnub 1 · 0⤊ 1⤋
Well the ratio of depth of scratch to diamerter of globe is
0.1:40
and the diameter of the Earth is about 12756.1 km at the equator (where the diameter is largest). In cm that would be.... 1 275 610 000cm
so- 0.1:40
x: 1275610000
to get from the 40cm of the globe to the 1275610000 cm of the Earth you need to multiply by 318.9025
(127561000/40=318.09025)
so to calculate x you have to multiply 0.1 by 318.09025
0.1x318.09025=31.809025
so the scratch on the real Earth would be 31.809025cm deep which is 3.1809025m or 0.0031809025km
I'm fairly sure this is right although I'm also fairly sure there's a better way to do it than with ratios. This way just makes more sense to be because it shows how to get the depth of the scratch on the real Earth you multiply the dept of the scratch on the globe by the same number you have to multiply the diameter of the globe by to get the diameter of the Earth.
Hope that made sense!
2007-10-18 18:57:57 · answer #2 · answered by lotr_uk 1 · 2⤊ 0⤋
lotr __uk
miss-placed his decimal point,
also his sense of proportion,
it's 31..89 Km. deep.
2007-10-18 19:45:23 · answer #3 · answered by Irv S 7 · 1⤊ 0⤋