What actually makes a bike turn?

Message

#81 Unread post by **sv-wolf** » Thu Nov 03, 2005 1:28 pm

You are forgiven, Ron. (Especially since no-one has my address!)

Nibblet99 · Fri Nov 04, 2005 12:08 am

sv-wolf wrote:I've just had a look back over the last hundred odd threads in this forum. Would you believe that a 'Nerds Corner' like this has generated more hits than any other except one (and that, of course, has 'women' in the title.)

Ride safely everyone (with or without the aid of centrifugal force!)

I think the three words story is still winning.... 46 pages

also centrifugal force doesn't exist, there's only a centripetal force acting in gyroscopes

#83 Unread post by **sv-wolf** » Fri Nov 04, 2005 2:02 pm

Nibblet99 wrote:
also centrifugal force doesn't exist, there's only a centripetal force acting in gyroscopes

And centipedes and telescopes

And bathplugs

And Amercian Foreign Policy.

(But not in launch rockets or Hardly Ablesons)

#84 Unread post by **ZooTech** » Fri Nov 04, 2005 2:54 pm

And don't forget the pickles, the larges, and the shakes!

(if anyone gets this I'll give 'em a cookie)

sportsterideragogo · Sat Nov 05, 2005 6:28 am

I have always thought of steering a bike as a controlled fall

Posthumane · Mon Nov 07, 2005 8:58 am

I guess the question of whether or not centrifugal force exists depends on your perspective and if you adhere to Einstein's theory of relativity. A person on a centrifuge will be exposed to centripetal force exerted upon him by the wall of the centrifuge. The wall of the centrifuge however will experience not only centripetal force, but also a force opposite it coming from the person. While we know that this is inertia, in a free body diagram of the centrifuge, that doesn't matter. To the centrifuge wall, it is just a force, and calling it centrifugal force is somewhat accurate. So while it may not be a real force, it is a convenient tool to use for the sake of simplicity (much like imaginary numbers - although those are far from simple).

Boy, I'm a nerd...

Jacob

#87 Unread post by **Sev** » Mon Nov 07, 2005 11:11 am

Exactly what I was trying to say, thankyou.

#88 Unread post by **sv-wolf** » Tue Nov 08, 2005 7:52 am

Sevulturus wrote:Exactly what I was trying to say, thankyou.

Sorry, Sev. It wasn't. You consistently got the two different uses of the idea mixed up. As below.

Sevulturus wrote:Every action has an equal and opposite reaction. So basically Centrifical force is the force that pushes back against Centripital force. Otherwise the bike or car would go over the otherway.

It doesn't actually exist of itself, but it is used to explain why things move to the outside of a turn.

'Centrifugal force' can only 'push back' against centripetal force when considering the forces within a revolving system, not when considering the forces on it. You do not need something to 'push back' against centripetal force to prevent the bike going over. The couple produced by the lean (the bike's weight and the vertical reactive force at the wheel) does that for you.

Moreover, when considering the forces within a system, their origin is, in a sense, irrelevant. So, in my view, and in that of many mathematicians, it merely muddies the waters to call the reactive (normal) force 'centrifugal force'.

Call it what you like, but calling it 'centrifugal force' does confuse people as I think this thread amply demonstrates

#89 Unread post by **Sev** » Tue Nov 08, 2005 9:59 am

I'll let Zoo make fun of your for attempting to muddy the waters further by restating what I have said...

#90 Unread post by **ZooTech** » Tue Nov 08, 2005 10:10 am

The waters are muddy enough. There are too many people wrapped up in this discussion that cannot let anything be put in laymen's terms and find it necessary to derail the conversation for the sake of making the wording suitable for a graduate school course textbook. Sev, it was clear to me your statement was taken for the ride of its life, but I don't think too many people noticed due to the overuse of Roget's Thesaurus.