m3 again

[gibby marr]

how do i work the the m3 of a tree trunk its 5 m long by 500 mm dia at one end and 450 mm at the other

 

can some on tell me hoe to work it out cheers

cheers gibby

[b101uk]

use 475mm dia

 

or ~0.8863839285714279m3

 

500mm dia = ~0.9821428571428563m3

450mm dia = ~0.7955357142857136m3

[treequip]

Area of a circle is 3.14 x the radius squared

 

The volume of a cylinder is the area x length

 

Assume an average dia. of 470mm

[.235 x. 235] x 3.14 x 5

3.6 cubic m

[Mesterh]

Online calculator

 

Cylinder

[b101uk]

Area of a circle is 3.14 x the radius squared

 

The volume of a cylinder is the area x length

 

Assume an average dia. of 470mm

[.235 x. 235] x 3.14 x 5

3.6 cubic m

 

 

err asuming timber was square at 0.5m x 0.5m that is a 0.25m2 x 5m = 1.25m3

 

i.e. W (0.5m) x H (0.5m) x L (5m) = volume

 

thus round timber of <500mm dia by 5m long must be less than 1.25m3

[treequip]

err asuming timber was squareat 0.5m x 0.5m that is a 0.25m2 x 5m = 1.25m3

 

i.e. W (0.5m) x H (0.5m) x L (5m) = volume

 

thus round timber of <500mm dia by 5m long must be less than 1.25m3

 

But it isn’t square, its round.

[b101uk]

3.6 cubic m

 

But it isn’t square, its round.

 

yes showing that its NOT 3.6m3 as you said given the square volume is still only ~1.25m3 then a cylinder MUST be less than that!

[treequip]

yes showing that its NOT 3.6m3 as you said given the square volume is still only ~1.25m3 then a cylinder MUST be less than that!

 

Apologies, I had plugged in a longer cylinder and didn’t check the cut and paste

[gibby marr]

help !!!!!!!!!!!!!!!!!!!!!

 

 

so that wid work out the tree trunk if i was to sell it as fire wood will be

3.6 m3 no way dose that work out or dose it

[b101uk]

help !!!!!!!!!!!!!!!!!!!!!

 

 

so that wid work out the tree trunk if i was to sell it as fire wood will be

3.6 m3 no way dose that work out or dose it

 

Treequips equation was right he just put the wrong m3

 

475mm dia / 2 = 237.5mm (0.2375m) radius

 

[0.2375m radius x 0.2375m radius] x 3.14 π (short Pi) x 5m length = 0.885577m3 volume

 

using longer Pi its ~0.8863839285714279m3

Edited February 13, 2010 by b101uk