Mother's Day - For those that do not live with mommy

Grandparents Day

Parent Teacher Confrence Day

Thanksgiving

Tax Day

I think there could be more.....

 

I was following an old farm truck, and every mile or so he would stop and whack the sides of the truck with a stick. After this happened a couple times, I got out and asked him what he was doing. "Well, I gots me a 1 ton truck, but I gots 2 tons o' chickens. So I gots to keep half of them flyin' in the air." Will his technique work?

 

Only over bumps....

That is almost as good as what weighs more

1 . A ton of Bricks

or

2. A ton of feathers

 

So you are stating that the rpm/angular velocity of the tip of an aircraft propeller or any other spinning mass is different than it is close to the hub?

I don't care if the radius of the spinning object is 100 miles, the tip will rotate at the same number of revolutions/time that the center will.

Please, one last chance, tell me you are kidding.....

 

I think he's talking about the treadmill plane.

 

I think you guys have WAAAAAAAAAY too much time on your hands.

Ok, now I'll add a question.....I keep seeing in peoples' sigs a box about overclocking to fight cancer. Anybody got a link where maybe I can get in on the fun????

 

No, I agree with you that the rpm at the hub and the tip are the same.

 

OK [QUOTE=Tradejoe28]The center of the axle velocity is the car's speed forward,QUOTE] I'll buy that I can't wrap my brain around this part. Due to different size tires on different vehicles, this cannot possibly be a constant .

 

this one is easy. a ton of 6000lb/square inch density concrete.

 

Go up and read my post above... ain't gonna explain it again. 'Cept to say that the hub and blades ARE spinning the same RPM. But the speed of the hub is much slower than the outside edge of the prop or rotor blade or any other object with a hub and something larger in diameter attached to it.

Go outside and do my experiment.

If the outside edge of a rotor moved the same speed as the hub, there'd be some serious warpage involved at some time or another.

It's elementary, my dear Watsons.

And, the question was about speed..not Revolutions Per Minute... two different factors.

 

You mean to say some people aren't getting it?

RPM is the same no matter what.

MPH will be different no matter what.

How about you tie a shotput to a rope, hold on to the rope, and spin yourself around in one spot. You and the shotput are ROTATING at the same rate of spin. But the shotput is TRAVELLING at a different rate of speed.

 

He is correct, the very top of the tire will betraveling at twice the vehicles velocity, the contact patch at 0 mph, and the axle at velocity...this is supposing you are under traction as well

To help wrap your head around that.

There are 2 basic types of velocity.. teh velocity you normally think of, linear velocity, and then there is angular velocity.

Now, the angular velocity of the tire, any point on it, the rim, the hub, is the same. The linerar velocity of the assembly is of course, the same, however that is an average velocity of all the parts.

Since the assembly is also rotating, the combined velocity, both angular and linear, at any given point in time, will not be similiar between two points of differant radii from the center, or even a differant angle from a given starting position of 0 degrees.

Now, to help in English.

a 30 inch street tire, like on my '02, and a 44 inch mudder, like what will be on my future bronco..

in order to go 1320 inches...um 110 feet?...the 30 incher has to rotate 44 times, while the 44 inch tire only has to rotate 30 times. now, if the two trucks are traveling at the same speed, obviously the 44 inch tire is rotating much slower.

Therefore, the 44 incher has a much lower angular velocity. however, it is maintaining the same linear velocity....btw....tanks and their treads are MUCH better example of this....and I dont know really whre to explain from here, except that a wheel powered vehicle moves fowards by placing more rubber/tread in front of the last rubber tread it laid down....much like how you put one foot in front of the other to move foward, except taht this is continuos.
now disregarding tire width, since we will pretend like that doesnt matter right now, no matter the size of the tire, in order to move foward 12 inches, it has to put down 12 inches of rubber, you with my crude explanation? well, if it needs to put down that 12 inches in a second, than at any location along the surface of the tire, the tire will be moving foward 12 inches of rubber in that second, now, if the tire is already moving foward at 12 inches / second, then if you look at the top of tire, it still needs to pass 12 inches of rubber / second to keep up the speed, add in its actual velocity and BAM! 24 inches / second instantaneous velocity.

 

Where is lostmybeer when you need him ? I think that is what happened to khadma . Have 2 questions for khadma to ponder .Do you think the earth is getting heavier or lighter and does air have mass ?

 

Glad someone agrees with me....

 

I think I stand corrected?