circle or sphere conversion/ratio
- Thread starter qazz
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mmm4444bot
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Hello qazz. Is this schoolwork?
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no, ive been out of school for 43 yrs, lol this is for my hobby . to make scaled inlays for my product
Otis
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Hi. By comparing diameters, we can obtain conversions factors. You'd like to know how much inch is needed on the small ball for each mile on the big ball, so we compare small to big.
\(\displaystyle \frac{8.5 \text{ inch}}{8000 \text{ mile}} = 0.0010625 \text{ inch per mile}\)
We multiply by that conversion factor, to scale miles to size.
200 [imath]\times[/imath] 0.0010625 = 0.2125
Therefore, a distance of 0.2125 inch (17/80ths) on the small ball represents 200 miles on the big ball.
If we were to compare large to small, instead, then we'd obtain a conversion factor telling us that every inch on the small ball represents about 941.17647 miles on the big ball.
Whatcha building?
\(\displaystyle \frac{8.5 \text{ inch}}{8000 \text{ mile}} = 0.0010625 \text{ inch per mile}\)
We multiply by that conversion factor, to scale miles to size.
200 [imath]\times[/imath] 0.0010625 = 0.2125
Therefore, a distance of 0.2125 inch (17/80ths) on the small ball represents 200 miles on the big ball.
If we were to compare large to small, instead, then we'd obtain a conversion factor telling us that every inch on the small ball represents about 941.17647 miles on the big ball.
Whatcha building?
lev888
Elite Member
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- Jan 16, 2018
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- 2,939
Set up a proportion: 8.5 inches to 8000 miles as y inches to x miles
8.5 inches/8000 miles = y inches / x miles
y = ( (8.5 inches)/(8000 miles) ) * x
Convert to the same units and divide to get the conversion factor.
i build custom pool cues, but working on a project for a friend,, u might have guessed, the 8000 miles is the earth. 8.5 is his projectHi. By comparing diameters, we can obtain conversions factors. You'd like to know how much inch is needed on the small ball for each mile on the big ball, so we compare small to big.
\(\displaystyle \frac{8.5 \text{ inch}}{8000 \text{ mile}} = 0.0010625 \text{ inch per mile}\)
We multiply by that conversion factor, to scale miles to size.
200 [imath]\times[/imath] 0.0010625 = 0.2125
Therefore, a distance of 0.2125 inch (17/80ths) on the small ball represents 200 miles on the big ball.
If we were to compare large to small, instead, then we'd obtain a conversion factor telling us that every inch on the small ball represents about 941.17647 miles on the big ball.
Whatcha building?
D
Deleted member 4993
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The responses above converts lines (perimeter). Be careful about conversion of projected areas
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