KN is this acurate?

[Ian Flatters]

Oh 1kN is equal to 101.971621298 kilograms of force.

[Ian Flatters]

and then just to complicate things, how do we count the force of a pendulum swing from a limb walk slip?

 

Now this is a whole thing that not even i really understand too well. Pendulum swing effect;

 

The period of swing of a simple gravity pendulum depends on its length, the acceleration of gravity, and to a small extent on the maximum angle that the pendulum swings away from vertical, called the amplitude. It is independent of the mass of the say your own weight hama. If the amplitude is limited to small swings, the period T of a simple pendulum, the time taken for a complete cycle, is:

 

T= 2x Pie (sorry cannot find symbol on here) divided by length of rope divided by the acelleration of gravity. which i think has been given on here already. Then as its a pendulum you must reduce gravitys force (verlocity) by 0.5% for every second after the 1 second has past as you should reach maximum velocity within a second as your downward force isn't increasing as such. Beacuse you kind of skimming along the downward force not trying to overcome it, like if you were falling?

 

hope this has helped but not my forte as such just got some help on this a while back when i was trying to work out if a rigging kit i used could pendulum swing at nearly the max SWL on a free running pendulum lowering type thing.

[arbclimber]

Now this is a whole thing that not even i really understand too well. Pendulum swing effect;

 

The period of swing of a simple gravity pendulum depends on its length, the acceleration of gravity, and to a small extent on the maximum angle that the pendulum swings away from vertical, called the amplitude. It is independent of the mass of the say your own weight hama. If the amplitude is limited to small swings, the period T of a simple pendulum, the time taken for a complete cycle, is:

 

T= 2x Pie (sorry cannot find symbol on here) divided by length of rope divided by the acelleration of gravity. which i think has been given on here already. Then as its a pendulum you must reduce gravitys force (verlocity) by 0.5% for every second after the 1 second has past as you should reach maximum velocity within a second as your downward force isn't increasing as such. Beacuse you kind of skimming along the downward force not trying to overcome it, like if you were falling?

 

hope this has helped but not my forte as such just got some help on this a while back when i was trying to work out if a rigging kit i used could pendulum swing at nearly the max SWL on a free running pendulum lowering type thing.

 

All very good info:thumbup1: but I would think the most important figure to work out would be the speed of swing at the moment you hit the main stem. With this type of fall its hitting the tree that hurts.

[Ian Flatters]

All very good info:thumbup1: but I would think the most important figure to work out would be the speed of swing at the moment you hit the main stem. With this type of fall its hitting the tree that hurts.

 

Yeah i thought about that but without doing it as such speed=dist/time i didn't really want to hazard a guess on that. As weight variances will give diff readings i kind of thought hmm bit too in depth for me that is.... i need someone else to work that out or leave a little bit of maths for hama...

[Ian Flatters]

All very good info:thumbup1: but I would think the most important figure to work out would be the speed of swing at the moment you hit the main stem. With this type of fall its hitting the tree that hurts.

 

Sorry got it

 

Fall=messy pants=stem=ouch.

 

Just couldn't resist.

[arbclimber]

Yeah i thought about that but without doing it as such speed=dist/time i didn't really want to hazard a guess on that. As weight variances will give diff readings i kind of thought hmm bit too in depth for me that is.... i need someone else to work that out or leave a little bit of maths for hama...

 

You are right, for this calculation there are a huge amount of variables such as weight but also things like friction at the anchor point and branches in the path of the swinging rope, which could hugely increase or decrease speed of swing. Trouble is there is no standard tree, height or setup which could really be used for this calculation either. Unless we use very basic principles, for example that you are in a tree with no branches, with your anchor vertically above you and you swing in a perfect vertical arc, the calculation will always be an educated guess.

Word of advice though, dont leave any maths to Hama, he's useless:001_tt2:

Sorry Hama, havent written anything derogatory about you in days so thought i'd best catch up.

[Shane]

One wee idea to help with the absolute basics.....

The Newton got its name because it is the weight of a typical apple (not a bramley)

like the one that fell on Isaac Newton's head when he was doing some formative pruning (not sitting beneath) his apple tree.

The fat bloke down the pub told me this so it must be true!

 

And if you do fall out of the tree and your rope snaps - fear not the fall will NOT hurt you

just beware of the sudden stop at the bottom.

 

And a philosophical gravity question for you clever bods...

If you bore a straight tunnel through the centre of the earth and out the other side,

assuming you were thermally insulated, if you jump down the tunnel would you oscillate in a yo yo manner until you eventually come to rest in the middle?

And for you genius peeps - how long would all this take?

Maybe we should get out and do some tree work...

[Ian Flatters]

One wee idea to help with the absolute basics.....

The Newton got its name because it is the weight of a typical apple (not a bramley)

like the one that fell on Isaac Newton's head when he was doing some formative pruning (not sitting beneath) his apple tree.

The fat bloke down the pub told me this so it must be true!

 

And if you do fall out of the tree and your rope snaps - fear not the fall will NOT hurt you

just beware of the sudden stop at the bottom.

 

And a philosophical gravity question for you clever bods...

If you bore a straight tunnel through the centre of the earth and out the other side,

assuming you were thermally insulated, if you jump down the tunnel would you oscillate in a yo yo manner until you eventually come to rest in the middle?

And for you genius peeps - how long would all this take?

Maybe we should get out and do some tree work...

 

Nope, due to gravitational pressure we would pop like a pea.

[arbclimber]

One wee idea to help with the absolute basics.....

The Newton got its name because it is the weight of a typical apple (not a bramley)

like the one that fell on Isaac Newton's head when he was doing some formative pruning (not sitting beneath) his apple tree.

The fat bloke down the pub told me this so it must be true!

 

And if you do fall out of the tree and your rope snaps - fear not the fall will NOT hurt you

just beware of the sudden stop at the bottom.

 

And a philosophical gravity question for you clever bods...

If you bore a straight tunnel through the centre of the earth and out the other side,

assuming you were thermally insulated, if you jump down the tunnel would you oscillate in a yo yo manner until you eventually come to rest in the middle?

And for you genius peeps - how long would all this take?

Maybe we should get out and do some tree work...

 

You cant have a tunnel through liquid matter is the obvious smart answer.

The slightly more technical answer would be that you could never actually find the true gravitational centre of the earth as the geometric centre would not be the gravitational centre. Gravity does not act on all matter of equal volume equally but instead on its mass. Neither is the centripetal force of gravity created equally by all matter. The calculations to work out the true gravitational centre of the earth are IMO impossible.

[Tony Croft aka hamadryad]

phew you boys sure can run with this! lol:laugh1: