Use dimensional analysis.
50 miles/hour * 1 hour/3600 seconds * 5280 feet/mile
The hour and mile units cancel out, leaving 73.3 feet per second.
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Dimensional analysis is the best answer - it explains the arithmetic. But it's also interesting and useful to know that Google will do the work for you. Just type:
50 miles per hour in feet per second
in the search box and read the answer:
50 miles per hour = 73.3333333 feet per second
(of course all those extra threes are much too precise for the data given).
Chat with our AI personalities
There are 3,600 seconds in an hour (60 seconds / minute * 60 minutes / hour). There are 5,280 feet in a mile. Therefore to convert feet / second into miles per hour, multiply by 3,600 / 5,280 (0.68) So 88 feet per second is 60 miles per hour. To go the other way (convert from miles per hour to feet per second), divide by 0.68.
First convert to feet per hour by converting the miles to feet by multiplying by 5280 as there are 5280 feet in a mile Now convert to feet per second by converting the hours to seconds, but as the time is on the bottom of speed = distance/time, divide by 3600 as there are 3600 seconds in an hour → 60 miles/hour = (60 × 5280) ÷ 3600 ft/s = 88 ft/s
(mph x 1.466 = feet per second). So, 70 mph x 1.466 = 102.62 feet per second.
The conversion factor is 1.466. So, 45 mph x 1.466 = 65.97 feet per second.
1 mile = 5,280 feet. 1 hour = 3,600 seconds (60 seconds / minute * 60 minutes / hour) Therefore 1 mile / hour = 5,280 feet / 3,600 seconds = 1.47 feet / second. So to convert miles per hour to feet per second, multiply by 1.47. And to convert feet per second to miles per hour, divide by 1.47. So for example 110 feet per second = 110 / 1.47 mph = 75 mph. And if you had it the other way, you'd take 75 mph * 1.47 to get 110 feet per second. BTW, if you're trying to figure out how fast a 75 mph fastball gets to a hitter, first figure out that it travels 110 feet per second, and then divide 60.5 (the number of feet from the mound to homeplate) by 110 (the number of feet the ball would travel in one second) and get 0.55 seconds. So a 75 mph fastball takes just over half a second to reach the batter.