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#1 2006-10-16 09:21:21
- long61999
- Guest
Calculating radius of a Sphere when volume is given
Hey, I'm really confused and have no idea. Could someone please complete one of these questions and take me through it. Many thanks
Calculate the Radius of each Sphere:
1. Volume of Sphere -= 250cm^3
2. Vol = 60cm^3
3. Vol = 154cm^3
#2 2006-10-16 09:38:13
- polylog
- Member
- Registered: 2006-09-28
- Posts: 162
Re: Calculating radius of a Sphere when volume is given
We need to use the volume of a sphere formula:
where r is the radius.
We have to re-arrange this formula, solve it for r:
One step at a time:
take the cube root of both sides:
So now we have a formula for the radius r when V is known:
Now using your specific numbers:
1. V = 250 cm^3
From the formula:
(approximately)
I assume you are allowed to use a calculator to work out these problems. 
Last edited by polylog (2006-10-16 09:40:08)
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