Techie question about ball / clubface impact

[DownAndOut]

Does the ball 'stick' to the clubface longer when its struck at greater speed?

For example, if you swung a  6 iron at 100mph  and it impacted the surface of the ball on the ball/target line (on a perfect 'in-square-in' swing path) would the ball 'ride' on the clubface longer than if it was swung at 50mph?

Edited December 8, 2016 by DownAndOut

[BristolGolf]

I would imagine that the laws of physics dictate that it should due to the compression of the ball, a faster swing will result in more compression so the ball will remain on the clubface that bit longer but I cant imagine it would be anything you could really notice? Think about a car impacting an object at 10mph and then the same at 30mph - the object would remain in contact with the car longer at a faster speed and the distance it as thrown once contact was broken would be further - I am not a real golf techy but I would suspect that is where increased distances with higher swing speeds comes from as well. 

I would be intersted in having a geek chime in to clarify if my assumptions are correct, or have I ASS-U-ME ?

[saevel25]

21 minutes ago, DownAndOut said:

Does the ball 'stick' to the clubface longer when its struck at greater speed?

The ball deforms, and will slide up the clubface a bit. Since it slides up the club face there is a force called friction applied to the ball. 

It doesn't stick in terms of like a magnet on a fridge. It sticks like how our shoes do not slide out from under us when we walk on concrete. 

Stick is not a good word to describe what is happening. 

23 minutes ago, DownAndOut said:

For example, if you swung a  6 iron at 100mph  and it impacted the surface of the ball on the ball/target line (on a perfect 'in-square-in' swing path) would the ball 'ride' on the clubface longer than if it was swung at 50mph?

Depends on a lot of things like the loft, compression of the golf ball, the surface of the clubface, angle of attack, ect.. I would say the difference is negligible in terms of results in golf. 

I could also say that maybe it's the opposite. Maybe the speed causes the ball to repel off the clubface fast enough that it has ball to clubface interaction. 

I am sure this has been studied. You might want to email a company like Ping or Titliest. They would have extensive research on topics like this. 

[Piz]

Does a basketball "stick" to the floor longer if you dribble faster?

[iacas]

13 minutes ago, DownAndOut said:

Does the ball 'stick' to the clubface longer when its struck at greater speed?

Not really. For full swings ball contact tends to last about 450 microseconds. That's true regardless of the club being used, so long as it's a full swing struck reasonably near the sweet spot.

13 minutes ago, DownAndOut said:

For example, if you swung a  6 iron at 100mph  and it impacted the surface of the ball on the ball/target line (on a perfect 'in-square-in' swing path) would the ball 'ride' on the clubface longer than if it was swung at 50mph?

AFAIK, not appreciably.

In fact, I don't even think a putt is too different. (I'll check on that with a few people later today.)

2 minutes ago, BristolGolf said:

I would imagine that the laws of physics dictate that it should due to the compression of the ball, a faster swing will result in more compression so the ball will remain on the clubface that bit longer but I cant imagine it would be anything you could really notice?

The ball doesn't really compress. It deforms. And there's a lot more to it than that - the ball immediately slows the clubhead while also instantly accelerating away. Longer clubs use effectively softer shafts… all of that has an effect. As we see from the face/path relationship, golf balls start closest to the face angle at higher swing speeds/less loft (i.e. more deformation) because more of the force is oriented "directly" away from the face in those instances.

Basically, as I understand things… a higher clubhead speed accelerates the ball more quickly, so while the ball deforms more, it also leaves faster. Those two things almost balance out most of the time to get to about 450 microseconds.

2 minutes ago, BristolGolf said:

Think about a car impacting an object at 10mph and then the same at 30mph - the object would remain in contact with the car longer at a faster speed and the distance it as thrown once contact was broken would be further - I am not a real golf techy but I would suspect that is where increased distances with higher swing speeds comes from as well. 

You'd think so (and also, cars deform a LOT more than a golf ball or clubface), but it's not necessarily the case.

This defies "common sense" in some ways, but makes sense from a physics perspective.

6 minutes ago, Piz said:

Does a basketball "stick" to the floor longer if you dribble faster?

Good one. I think people will have a good chance of grasping that one.

[DaveP043]

My first reaction was that the ball must stay in contact with the clob longer when the impact velocity was higher.  However, and after reading @iacas response, I can see that the time shouldn't change much.  Its analogous to the natural frequency of a pendulum.  A pendulum will swing at the same frequency, whether its arc is long or short.  For a long arc, the peak velocity is greater, but the frequency is the same.  The compression (or deformation) and subsequent rebound of a golf ball should work the same way, I think.  The long arc of the pendulum would correspond to the greater deformation of the higher-velocity impact.

[14ledo81]

If you look at it on the extreme slow side, the ball would "stick" for much longer.  Obviously no one would ever swing that way, so it doesn't really matter.

[DownAndOut]

Many thanks for all your replies. So if the contact period is around the same at 450 microseconds, then I am assuming the ball that is in continual contact with the faster moving clubface will move 'together' a  longer distance (until the ball reaches its maximum deformation before leaving that clubface). So the ball will actually leave the clubface at a point further in the swing path from its original point of impact (ie. the clubface would be pointing slightly more to the left of ball target line). A slower moving clubhead speed would mean the ball would leave the clubface less left of the ball-target line.

Edited December 9, 2016 by DownAndOut

[Piz]

450 microseconds is too brief a time to produce that drastic a result.  For a better explanation than I am capable of check out www.tutelman.com.  There are some entertaining articles there about collisions, force multipliers, and so forth, written by a physicist/golfer from New Zealand.    Cheers.

[iacas]

Assuming centered contact, sure. But even at 150 mph you're talking about… just over an inch.

I think when we talked with Tuxen it amounted to a max of ~1.5 degrees for the entire interval with a SUPER high rate of closure.

There's a video somewhere. We were actually the first people to point out to him that a closing clubface tilts the spin axis toward a fade.

[Missouri Swede]

2 hours ago, iacas said:

We were actually the first people to point out to him that a closing clubface tilts the spin axis toward a fade.

Due to gear effect? (Like the opposite of a toe strike producing an opening clubface-->draw gear effect?)

[iacas]

1 hour ago, Missouri Swede said:

Due to gear effect? (Like the opposite of a toe strike producing an opening clubface-->draw gear effect?)

Kinda, right.

[saevel25]

8 hours ago, iacas said:

Kinda, right.

My best guess it has to do with how relative center of mass changes in space as the face angle and path changes. . 

 

[paininthenuts]

23 hours ago, DownAndOut said:

Does the ball 'stick' to the clubface longer when its struck at greater speed?

For example, if you swung a  6 iron at 100mph  and it impacted the surface of the ball on the ball/target line (on a perfect 'in-square-in' swing path) would the ball 'ride' on the clubface longer than if it was swung at 50mph?

No