A perfect circle?

[Old Expat Beast]

Been trying to get my head around this thought. As the Milgauss second hand's arrow is slightly offset from the centre of the dial (due to the lightning bolt shape), does it still describe a perfect circle within the circumference of the dial?

[Baselman]

Yes the hand length doesn't change in its rotation so perfect circle

[padi56]

Originally Posted by Old Expat Beast

Been trying to get my head around this thought. As the Milgauss second hand's arrow is slightly offset from the centre of the dial (due to the lightning bolt shape), does it still describe a perfect circle within the circumference of the dial?

If it moves 360 degrees around the dial then that is a circle no matter the shape of the dial watch hands

[Old Expat Beast]

It's illogical I know, but somehow I can't get to grips with a three-stepped hand performing three equal circles within an outer circle. I must be feeble minded.

[JGX]

Originally Posted by Old Expat Beast

It's illogical I know, but somehow I can't get to grips with a three-stepped hand performing three equal circles within an outer circle. I must be feeble minded.

Does this (very rough and quick photoshop example) help?:

[Old Expat Beast]

Originally Posted by JGX

Does this help?:

Attachment 437775

Um....kind of. Thanks.

[Baselman]

The hand is FIXED the hand length is FIXED the steps are FIXED so every second of rotation equals same position as previous second - law of physics and geometry mean perfect circle rotation.

[Cc1966]

Remember Adam, the lightning bolt hand starts in the center (point A) and ends at the triangle (point B). Now just connect the points mate as the hand is not made of rubber!

[Cesium133]

OP, here's something else to think about...

-The base of the second hand rotates at shorter length than than the arrow at the end. Notice the size of the red circle (base) and the size of the green circle (arrow).

-It takes the entire second hand 60 seconds to make 1 complete rotation. But the arrow end travels a greater distance than the base end, as illustrated in the photo.

-Doesn't that mean the arrow end is traveling at a faster speed than the base end since it covers a greater distance in the same amount of time?

Have fun thinking about that one...

[Old Expat Beast]

Originally Posted by Cc1966

Remember Adam, the lightning bolt hand starts in the center (point A) and ends at the triangle (point B). Now just connect the points mate as the hand is not made of rubber!

Ok, that works. Thanks

[joe100]

Think about this: if the second hand were long enough, ie VERY long, the end at the cannon pin would be rotating at 60 seconds a minute, but the tip would break the sound barrier.

Don't you just love science?

[iazrollie]

Exactly. Yet all points on the hand travel at the same revolutionary speed! Same rpm's at every point on the hand.

[Thatguy]

Originally Posted by joe100

Think about this: if the second hand were long enough, ie VERY long, the end at the cannon pin would be rotating at 60 seconds a minute, but the tip would break the sound barrier.

Don't you just love science?

True,but how long would it have to be? Anyone feel like doing the math?

[joe100]

Originally Posted by Thatguy

True,but how long would it have to be? Anyone feel like doing the math?

It's an easy formula:
a = v2
__
r

The speed of sound at sea level is 1,126 fps

Solve for r

Good luck!