Measuring the Speed of a Pitch
Date: 06/11/2002 at 01:50:16 From: Josh Subject: how fast can I throw a baseball Our school doesn't have a radar gun for determining how fast a pitcher can throw a baseball. I need a formula so I can figure this out myself. I know the distance from the mound to the plate is 60 feet 6 inches. I want to get the miles per hour by using a stopwatch to measure the time the ball takes to travel this distance. Do you have such a formula?
Date: 06/11/2002 at 09:14:33 From: Doctor Ian Subject: Re: how fast can I throw a baseball Hi Josh, It's handy to know that 88 feet per second is the same speed as 60 miles per hour, so if you know that the ball travels 60.5 feet in x seconds, you can convert that to miles per hour this way: 60.5 feet 60 miles/hour 60.5 * 60 --------- * -------------- = --------- miles/hour x seconds 88 feet/second x * 88 Note that a ball thrown at 60 mph will take about 0.69 seconds to get to the plate. What happens if your measurement is off by 1/10 of a second? If you add 1/10 of a second, the measured speed will be 52.2 mph; if you subtract 1/10 of a second, the measured speed will be 69.9 mph. You also might want to take into account that 60'6" is the distance to the pitcher's plate; but the pitcher normally releases the ball after stepping and reaching forward from there. Does this help? - Doctor Ian, The Math Forum http://mathforum.org/dr.math/
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