This isn’t going to be a big physics thing. I don’t know enough to write it, and would you understand it if I did?<\/p>\n
This is about phonograph records. I know, I date myself, but they illustrate the point perfectly.<\/p>\n
If you watch a spinning phonograph record, you would note that the part near the spindle turns very slowly, and the part at the far edge races around the turntable.<\/p>\n
That’s because they have to make one revolution in the same amount of time, but with different distances to go. <\/p>\n
On a 33-1\/3 RPM recored, a spot a half-inch away from the spindle travels at a speed of 105 inches per minute. A spot on the far edge of the record, six inches away from the spindle, travels at 1,256 inches per minute. *<\/p>\n
O.K.? So let’s talk about golf clubs. My 7-iron is 38″ long, and my driver is 44.5″ long.<\/p>\n
If I swing them at the same speed, the clubhead of the driver, because the driver is a longer club, should be going 17% faster than the clubhead of the 7-iron.<\/p>\n
That’s a theoretical analysis. Here is some actual data.<\/p>\n
Average LPGA swing speed<\/a> with a 7-iron is 76 MPH. The ball carries 141 yards at that speed. You can probably hit a 7-iron that far.<\/p>\n That same swing, applied to a driver, becomes 94 MPH, which is roughly 24 % faster. That yields a a carry distance of 218 yards. Add some roll-out and you have yourself a pretty decent drive … <\/p>\n … by swinging your driver the same as you do your 7-iron!**<\/p>\n Where does the extra clubhead speed come from? Why not just 17% faster?<\/p>\n Remember that the golf swing is a dual-lever motion. The arms, swinging from the shoulders, provide the 17%. The club, swinging from the hands to the clubhead, proved the remaining 7%.<\/p>\n But that’s not the point. The point is that your 7-iron swing is your driver swing. Let the design of the club (longer shaft, less loft) do the work.<\/p>\n ——<\/p>\n * Scientists used a phonograph record to verify Einstein’s Special Theory of Relativity. A “clock” on the edge of the record does run slower, because it is going faster, than a “clock” next to the center of the record. The difference is really, really, really small, but it’s there.<\/p>\n ** Red typeface is the Internet equivalent of writing something on a large polo mallet and hitting you over the head with it.<\/p>\n","protected":false},"excerpt":{"rendered":" This isn’t going to be a big physics thing. I don’t know enough to write it, and would you understand it if I did? This is about phonograph records. I know, I date myself, but they illustrate the point perfectly. If you watch a spinning phonograph record, you would note that the part near the … Continue reading Simple Mathematics of the Driver<\/span>