Centrifical vs Centrifugal Force

[Champcar]

In my Comm groundschool one of our head CFI's told us that centrifical force does not exist and that is is centrifugal force. I thought he was nuts for coming up with that crap but google may be proving him right. What do ya'll think?

[Minnesota_Flyer]

Perhaps you should find a dictionary, look up "centrifical", and let us know what you find.

Webster's defines "centrifugal" as "directed or moving away from a center or axis" or "operated by centrifugal force."

Oddly, "centrifical" does not have an entry.

[Stone Cold]

Do you mean centrifugal vs. centripetal forces?

[Champcar]

Originally Posted by txpilot

Do you mean centrifugal vs. centripetal forces?

Negitive

[Flysher]

technically speaking, it doesnt truely exist, reference this thread

http://forums.jetcareers.com/showthread.php?t=32512 (Overbanking v. Adverse Yaw)

[Champcar]

Originally Posted by Minnesota_Flyer

Perhaps you should find a dictionary, look up "centrifical", and let us know what you find.

Webster's defines "centrifugal" as "directed or moving away from a center or axis" or "operated by centrifugal force."

Oddly, "centrifical" does not have an entry.

Sorry, never heard of centrifugal

[Hacker15e]

Originally Posted by Champcar

In my Comm groundschool one of our head CFI's told us that centrifical force does not exist and that is is centrifugal force.

Spelling error. You've heard of a "centrifuge", right? It's called that for a reason (instead of a "centrific").

More important is the discussion about centrifugal vs centripetal force -- one that was debunked in high school physics class.

[TXaviator]

"centrifugal force" does not exist

end discussion

[Champcar]

Originally Posted by TXaviator

"centrifugal force" does not exist

end discussion

lol.

I must be a retard, I know what a centrifuge is but i remember the bucket full of water from middle school science and calling it centrifical force (unless i cant spell) but I had NEVER heard of centrifugal.

[B767Driver]

Centripetal force is really the force present in allowing the airplane to fly along a curved path, i.e, make a turn.

Centrifugal force exists...and is counter to centripetal...but doesn't act on the airplane...otherwise they would cancel each other out and negate the turn.

It's my understanding that the force you feel as you turn in a car is not centrifugal force...but the centripetal force pushing you to the inside of the turn. Otherwise...you would remain on a line tangent to the turn and continue in a straight line.

Seagull...??? Is this accurate?

[Flysher]

ok, theres centripetal and centrifugal but no such thing as centrifical. The last two sound similar though so i can where you might have got that.

[Stone Cold]

Originally Posted by Champcar

Negative

Helped you out there...

As far as your question, I guess we've come to the conclusion I was going to tell you. Neither one exists. Centrifugal forces, in the physics courses I've taken (long long time ago) does not exist (at least in most circumstances, and for aerodynamics discussion). Centrifical is just a misspelling, I am assuming. Centripetal force is what turns an airplane.

http://observe.arc.nasa.gov/nasa/spa...trifugal1.html

[Hacker15e]

Originally Posted by Champcar

lol.

I must be a retard, I know what a centrifuge is but i remember the bucket full of water from middle school science and calling it centrifical force (unless i cant spell) but I had NEVER heard of centrifugal.

If you pronounce the "g" like a hard "c", it's the same thing. It's a mis-pronounciation (and mis-spelling) of the actual word. "Centrifugal" is the actual word, "centrifical" is the phoenetic bastardization.

Just like people who manage to pronounce an "r" when saying "wash" (e.g. "warsh").

[Realms09]

Originally Posted by B767Driver

Centripetal force is really the force present in allowing the airplane to fly along a curved path, i.e, make a turn.

Centrifugal force exists...and is counter to centripetal...but doesn't act on the airplane...otherwise they would cancel each other out and negate the turn.

It's my understanding that the force you feel as you turn in a car is not centrifugal force...but the centripetal force pushing you to the inside of the turn. Otherwise...you would remain on a line tangent to the turn and continue in a straight line.

Seagull...??? Is this accurate?

You have the right of it. Centrifugal force, along with coriolis force, are apparent body forces that arise when one is travelling along inside an accelerated reference frame (such as a reference frame attached to a turning aircraft). These apparent forces disappear in an inertial frame (a frame that is not accelerating, such as a stationary observer on the ground).

True forces are present in all reference frames. So in the inertial ground frame, there is a centripetal force and the plane moves in a circle. Within the accelerated reference frame of the plane, the centripetal force acting on the pilot exactly counteracts apparent centrifugal force, because the pilot is not accelerating relative to the plane (assuming you're just sitting in your seat).

It only makes sense to talk about these apparent pseudoforces when you are referring to the accelerated frame. So, the apparent centrifugal force DOES act on the aircraft and DOES negate the turn, but only WITHIN the accelerated reference frame - the plane does not turn relative to itself. If the plane turns 15 degrees to the left, so does the plane's reference frame, and within that frame, nothing has changed.

[seagull]

Originally Posted by B767Driver

Centripetal force is really the force present in allowing the airplane to fly along a curved path, i.e, make a turn.

Centrifugal force exists...and is counter to centripetal...but doesn't act on the airplane...otherwise they would cancel each other out and negate the turn.

It's my understanding that the force you feel as you turn in a car is not centrifugal force...but the centripetal force pushing you to the inside of the turn. Otherwise...you would remain on a line tangent to the turn and continue in a straight line.

Seagull...??? Is this accurate?

Tgrayson will have fun with this one, but I would say that centrifugal force does not exist at all. Essentially, if you are in a car and the car makes a hard turn, you feel pressed against the outside of the turn. What is going on is that your body is independent of the car, and it wants to continue in a straight line, but the car is changing its path, so you hit the outside side of the turn as you move along going straight. The "force" of you hitting the outside is what is referred to in common venacular as "centrifugal force", but it is not a "force" at all, but just the obvious result of what I described above. No "force" is being applied to you, except for any that the car is applying to "force" you to turn with it! Hopefully a reasonable response after a couple of brews!

[fish314]

Originally Posted by seagull

Tgrayson will have fun with this one, but I would say that centrifugal force does not exist at all. Essentially, if you are in a car and the car makes a hard turn, you feel pressed against the outside of the turn. What is going on is that your body is independent of the car, and it wants to continue in a straight line, but the car is changing its path, so you hit the outside side of the turn as you move along going straight. The "force" of you hitting the outside is what is referred to in common venacular as "centrifugal force", but it is not a "force" at all, but just the obvious result of what I described above. No "force" is being applied to you, except for any that the car is applying to "force" you to turn with it! Hopefully a reasonable response after a couple of brews!

This is exactly right. What someone said above about "apparent" forces is correct. An "apparent force" (like "centrifugal force") is a result of your whole frame of reference being under the influence of an opposite force...

To put that clearer, imagine a car turning in a circle. The car is experiencing a force towards the center of the circle, otherwise it would continue in a straight path. This force is centripetal-- a force towards the center of the circle.

Now if you are INSIDE the car, you seem to feel as though you are pushed OUT from the center of the circle, but what is really happening is that the rest of the car is being pused toward the center of the circle, and you are not. It feels as though you are experiencing a force to the outside, because your whole reference frame (in this case the car) is experiencing an opposite force (to the inside). You aren't really experiencing a "real" force, what you notice is only an "apparent" force. This is what centrifugal force is. It's not really a force at all, but rather an "apparent force" that objects experience when they are in a frame of reference, where the whole frame of reference is accelerating or experiencing a force.

[TonyC]

Originally Posted by Champcar

I must be a retard, I know what a centrifuge is but i remember the bucket full of water from middle school science and calling it centrifical force (unless i cant spell) but I had NEVER heard of centrifugal.

Think back to that bucket. Imagine a man spinning around holding a bucket half full of water. His arm is outstretched, parallel to the ground, and the bucket is perpendicular to the ground. In other words, if the bucket were at rest, the water would pour out onto the ground. But it doesn't. It remains "suspended" at the bottom of the bucket.


Besides gravity, 2 forces act on the water and the bucket. The first we know from an introductory study of Newton. A body at rest tends to remain at rest, and a body in motion tends to remain in motion, until acted upon by some outside force. We usually refer to this tendancy as inertia. The bucket of water wants to continue to move in the direction in which it is currently moving. If you could freeze-frame the motion, the direction it wants to travel is exactly perpendicular to your outstretched arm.

So then, why does it not travel in this direction? Because your outstretched arm also imparts a force to the bucket in the direction of the center of this spinning man and bucket combo. Your arm pulls the bucket toward your body. It is this force that transforms the straight line, unaccelerated motion of the bucket, into a circular motion. This force is known as centripetal force.


Wanna know what happens without centripetal force? Let go of the bucket. Then it's all inertia and gravity.






.

[SteveC]

Originally Posted by TonyC

Wanna know what happens without centripetal force? Let go of the bucket. Then it's all inertia and gravity.

Yeah buddy. It's all fun and games until someone gets their eye put out.