0
   

Pi r^2xh

 
 
dadpad
 
Reply Sun 20 Mar, 2011 06:31 am
volume of a cylinder
Pi r^2xh
which one first?



  • Topic Stats
  • Top Replies
  • Link to this Topic
Type: Question • Score: 0 • Views: 1,902 • Replies: 7
No top replies

 
littlek
 
  2  
Reply Sun 20 Mar, 2011 06:46 am
@dadpad,
PEMDAS

PArenthesis come first (you don't have any)
Exponents come second (radius squared)
Multiplication and Division come next, from left to right (Pi x your product of rad sq x height)
dadpad
 
  1  
Reply Sun 20 Mar, 2011 09:10 am
@littlek,
thanks K
now a test for you

Its not propely a cylinder

Its more like a cone with the top cut off.
How can I calculate a volume?
contrex
 
  1  
Reply Sun 20 Mar, 2011 09:22 am
@dadpad,
dadpad wrote:

a cone with the top cut off.
How can I calculate a volume?


V = 1/3 * pi * (R1^2 + R1 * R2 + R2^2) * h
R1 = Radius of the base
R2 = Radius of the top
h = height of the truncated cone
littlek
 
  1  
Reply Sun 20 Mar, 2011 01:24 pm
@dadpad,
I'm not sure I get the image, is it a straight up cone ? Then your above formula dived by 3 would work. Otherwise (if it has two blunt ends) go with contrex's formula.
0 Replies
 
dadpad
 
  2  
Reply Sun 20 Mar, 2011 04:10 pm
Thanks contrex.

does this work?
r1 + r2 + r3 /3 = avg r
pi (avgr)^2 x H

lil K shape is similar to this. wider at base than top but top is not a point
.......... /\ ........
littlek
 
  1  
Reply Sun 20 Mar, 2011 04:12 pm
@dadpad,
no. At least your formula does not equate to contrex's formula.
0 Replies
 
contrex
 
  1  
Reply Sun 20 Mar, 2011 04:28 pm
@contrex,
V = 1/3 * pi * (R1^2 + R1 * R2 + R2^2) * h

or put another way...

The volume of a circular cone frustum (a cone with the apex sliced off parallel with the base) is

http://upload.wikimedia.org/math/0/3/5/035329cf00942725a35baee2f417bdc2.png

http://en.wikipedia.org/wiki/Frustum


0 Replies
 
 

Related Topics

Amount of Time - Question by Randy Dandy
logical number sequence riddle - Question by feather
Calc help needed - Question by mjborowsky
HELP! The Product and Quotient Rules - Question by charsha
STRAIGHT LINES - Question by iqrasarguru
Possible Proof of the ABC Conjecture - Discussion by oralloy
Help with a simple math problem? - Question by Anonymous1234567890
How do I do this on a ti 84 calculator? - Question by Anonymous1234567890
 
  1. Forums
  2. » Pi r^2xh
Copyright © 2021 MadLab, LLC :: Terms of Service :: Privacy Policy :: Page generated in 0.03 seconds on 01/24/2021 at 06:30:58