A human punch, like a boxing punch, does not have the benefit of wrist rotation and finger extension. Compare simply tossing an object, like a shotput (analogous to a punch), with a baseball pitch (analogous to an atlatl).
The atlatl:
The pitcher’s arm and fingers act as a “fast-moving extension of the throwing arm, increasing the length of the lever.”
In this case the gases behind the projectile (the actual source of propulsion) are moving at least as fast as it does when it leaves the barrel.
Gesundheit.
It is a series of combined movements that allows the accelleration of a baseball to pro speeds.
Think of it like throwing a ball forward from a moving car. The car is moving 40 mph and you throw the ball hard enough to go 30 mph forward. Briefly the ball itself is moving 70 mph.
A series of movements including hip pivot, shoulder rotation, arm extension, wrist movement, hand movement and finger movement.
This is not an actual breakdown, but more of an illustration
pivoting hips 10 mph
shoulder rotation +25 mph
arm extension +15 mph
wrist pivot +10 mph
hand movement +5 mph
finger movement +10 mph
=75mph
Through training you can learn to optimize that flow of events to maximize pitching speed.
No cites beyond a discussion with a friend who was a relief pitcher for a AAA team for a couple years.
poor angle or technique at any point in the series removes a chunk of that speed. Pro pitchers are analyzed and drilled on how to optimize that
Nor is your comment, unless you have exploding fists.
It’s time for Una Persson to solve the mystery for us.
W-e-l-l-l the projectile is not going to travel at any 100mph unless the energy
from detonation is concentrated by the barrel, so I would consider the analogies
to be something like:
barrel~pitcher’s fingers, and
detonation~the rest of the pitcher’s body,
but hey, my only physics course was in Grade 9.
Google informs us that the formula for kinetic energy is:
KE = 1/2MV^2
Since energy depends on velocity *squared *I suspect that is part of the solution
we are looking for.
Una! Help!
Towards the release of the ball there is not a direct ‘solid’ connection between ball and hand. This can lead to a force multiplication almost like changing a gear ratio where the power of the hand is transfered into speed of the ball. This I believe would happen as the ball comes off the fingers, the ball would ‘roll’ off the fingers which imparts more speed then the hand it moving.
A 90 mph fastball will have about 85ft# of kinetic energy. The longer the baseball is being accelerated the more energy will be imparted to it.
I shoot arrows through a chrono while testing my bows. If I use an active bow hand, throw my hand forward upon release of the string I can add up to 20 fps to the speed of an arrow.
Right – we can’t equate the speed of the hand when punching with the speed of the fingers) when throwing a ball.
My money is on the claim that the hand is going 90 MPH when it releases the ball, and the ball never goes faster than the hand releasing it. (In the other thread I mentioned the possibility of the ball going faster due to spring effects. I do believe it’s possible for a tennis ball to leave the racket going faster than the head of the racket, and even faster than the strings where they contact the ball. But I doubt this is a factor in a baseball pitch.)
Good point, but that happens with the punch, too. It depends on the type of punch. For a boxer’s jab, which has to happen without a windup (that would ‘telegraph’ the punch), this is minimal. But I’m sure there are punches when one sees one’s opponent is stunned, and one gets a chance to really let fly. It’s not clear which kind of punch the 32MPH above is for.
I don’t buy this. The fingers could definitely flick at the release to impart more speed, but that’s still the body going the same speed as the ball, at release. How do we get any additional movement from the baseball by NOT touching it?
How can the process of imparting spin make the ball go faster (if as discussed above, the ball can’t convert rotational momentum into linear momentum – which I believe it can but not enough to matter here) ? If the ball is going faster than the fingers and rolls off them, that would slow it down, not speed it up.
There are definitely things in physics that are counter-intuitive. (Just hold a rotating wheel by its axles and impart a force to turn it, for example.) But if there’s anything special going on here, I want a much more specific and technical explanation, to be convinced.
Interesting, but I don’t think this is relevant.
The bow and arrow is a different case because energy is stored in the arch of the bow. Moving your fist has two effects: it can add energy to the spring (the arching of the bow), and it adds forward velocity. How does that apply to a pitching arm? Human muscles (unlike Kangaroo leg muscles) don’t store energy from an external source, like springs do.