FT/S to MPH: How To Convert Feet per Second to Miles per Hour

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In 1999 NASA was set to launch the Mars Climate Orbiter into space. Instead, the orbiter burned and broke into pieces, costing NASA $125 million.

This mistake happened because no one converted NASA 's calculations into metric units. This led to incorrect calculations that ended in disaster.

As this story shows, having the right measurements can make or break certain projects. In some cases, it can even be life or death. Though it's possible to use guesses and estimates when doing unit conversions, most times you'll need the most accurate measurements possible.

This is especially true when it comes to cars, which you usually measured in MPH, or miles per hour. If you want to understand how to convert ft/s to mph then we've got the perfect guide for you.

What Are Miles Per Hour and Feet Per Second?

Miles per hour refers to a unit of velocity and speed. Velocity refers to the speed of something moving in a specific direction. This measures the number of miles an object travels in an hour. 

Both the British Imperial system and the US customary units use miles for length. The British imperial system is a measurement system that began in Britain in 1824. In 1965, the metric system replaced this system.

The system uses inches, feet, yards, and miles as measures of length and weight. The British imperial system not widely used anymore. Though, measurements like miles and pints are still employed.

The United States customary system came from the British imperial system. This means it uses measurements like inches, feet, and miles. These units of measurements originated in ancient Rome, Saxon, and Carolingian.

Though the systems currently used in the united states and Britain are very similar, there are differences that came about because of the Weights and Measures Act of 1824. This act radically changed the way that these units were counted.

The United States has been lagging behind the rest of the world when it comes to our units of measurements. The United States is one of the only countries to not switch to the metric system. Other countries include Liberia and Myanmar.

Keep in mind the United States uses customary units for most commercial activities. This includes things like shopping and for personal activities like weighing. The US does use the metric system for things like government and military activities. The United States also uses it for medicine, science, and certain private industries.

When Should You Use Ft/s?

Feet per second is rarely used in most industries and you are unlikely to run into it often. It isn't considered to be a common measure of speed or velocity.

Though it is uncommon when measuring things like car speed and wind, in science its notation is physics and chemistry. These units of measurement can be especially helpful with objects that move very slowly. It can also be abbreviated to fps and its scientific notation is ft s⁻¹.

Another time where ft/s is used is when measuring acceleration. This is expressed as feet per second squared and is abbreviated as ft/s^2 or ft s^−2.

When Should You Use MPH to Measure?

Miles per hour is often abbreviated to mi/h or mph and is typically used in only a small portion of the world. In fact, only 9% of the world uses mph instead of the more commonly used kph. Interestingly, many countries in the Caribbean still use miles.

Many countries like the Bahamas, Burma, Antigua, Nevis, and St.Kitts all use miles per hour.

you will typically see these units and numbers on highways to indicate speed limits and the number of miles to a destination. There are also options if your car is made in Japan or Europe that allow you to change your speedometer to mph. 

These devices include using an inline converter or changing the dial readout. The inline converter is a device that you purchase that changes your speedometer in real-time. The other option you have is to change the dial manually. 

Though this can be done by many professionals in the auto repair industry, it is not a possibility for every car on the market.

Things to Keep in Mind While Converting

If you're looking to get a more thoughtful explanation of how to convert, we first have to define some terms that deal with measurements. One thing to keep in mind is that the feet to miles conversion rate is 5,280 feet per one mile. Also in one hour, there are 3,600 seconds. 

If you want to know how to calculate miles per hour from feet per second you first have to keep in mind the conversion number. The way to convert it is to multiply feet per second by 3600/5280 which, when reduced, gives you 15/22 or 0.6818. This means that our ft/s to mph equation is ft/s *.6818.

This means that if we want to convert 10 ft/s to mph, we simply multiply 10*.6818 to get 6.818 mph. 

There is also another way to convert ft/s to mph and that is to divide by 1.467. If this seems complex, lets first go over the formula to calculate ft/s to mph. To do this, we divided 15/22 to get 0.6818. If we then divide 1 by this number, we get 1.4667. If we then divide 1.4667 by ft/s we get the mph.

Now let's do a calculation to convert larger numbers. If we wanted to convert 2,555 ft/s to mph then we would either multiply by .6818 to get 1742.045 mph or divide by 1.467.

Easy Ways to Convert Ft/S to MPH

One of the easiest ways to convert ft/s to mph is to find a simple online calculator to do it for you. These calculators work by processing numbers you input and outputting a correct number. Luckily, there are tons of options if you want to learn more about how to find the perfect online conversion calculator. 

Another easy way to convert feet per second to miles per hour is to use a conversion chart. Below are some of the most common conversions. All you have to do is look up the chart and confirm your conversion.

  • 1 ft/s = 0.6818 mph
  • 2 ft/s = 1.3636 mph
  • 3 ft/s = 2.0455 mph
  • 4 ft/s = 2.7273 mph
  • 5 ft/s = 3.4091mph
  • 6 ft/s = 4.0909 mph
  • 7 ft/s = 4.7727 mph
  • 8 ft/s = 5.4545 mph
  • 9 ft/s = 6.1364 mph
  • 10 ft/s = 6.8182 mph
  • 11 ft/s = 7.4999 mph
  • 12 ft/s = 8.1818 mph
  • 13 ft/s = 8.8636 mph
  • 14 ft/s = 9.5455 mph
  • 15 ft/s = 10.2272 mph
  • 16 ft/s = 10.9090 mph
  • 17 ft/s = 10.9091 mph
  • 18 ft/s =11.5909 mph
  • 19 ft/s = 12.9545 mph
  • 20 ft/s = 13.6363 mph
  • 25 ft/s = 17.0455 mph
  • 30 ft/s = 20.4545 mph
  • 40 ft/s = 27.2727 mph
  • 50 ft/s = 34.0909 mph
  • 75 ft/s = 51.1363 mph
  • 100 ft/s = 68.1818 mph
  • 250 ft/s = 170.4545 mph
  • 500 ft/s = 340.9090 mph

Though there are more thorough conversion charts, these are some of the most common ft/s that you will need to look up.

Other Helpful Conversions

As we've stated earlier, measurements like mph and ft/s are being used less frequently in favor of the metric system. This makes it even more important to know how to perform conversions between the imperial system and the metric system. 

The metric system is a system of units that uses grams (for weight), meters for distance, and liters (for volume). As opposed to miles, this system uses kilometers and 1 mile is around 1.60934 kilometers. This means that the conversion for mph to kph is mph *1.60934. 

This means that if we want to convert units, we can either convert ft/s directly to kph or convert it to mph and convert that to kph.

Below we'll show you how to do both the direct conversions and indirect conversions. The conversion factor to convert feet per second to kilometers per hour is 1.09728. This means that if we want to convert 20 ft/s to kph, we simply multiply 20 by 1.09728 this gives us 21.9456 kph.

If we want to use an indirect method to convert ft/s to kph, then we can convert the ft/s to mph and then convert that to kph. This means that if we want to convert 750 ft/s to kph, we need to multiply 750 by 0.6818 to get 511.364 mph, then multiply that by 1.60934 to get 822.9606 kph.

Now we want to include several mini charts that will help you convert these imperial units of ft/s to metric kph.

  • 1 ft/s = 1.09728 kph
  • 2 ft/s = 2.1945 kph
  • 3 ft/s = 3.29184 kph
  • 4 ft/s = 4.3891 kph
  • 5 ft/s = 5.4864 kph
  • 6 ft/s = 6.5836 kph
  • 7 ft/s = 7.6809 kph
  • 8 ft/s = 8.7782 kph
  • 9 ft/s = 9.8755 kph

Another use for these kinds of conversions and measurements is to convert backward from metric to imperial. This simply requires that we divide the ft/s by 1/1.09728 or multiply by 0.9113. To test this, let's convert 400 kph to ft/sc. We set up the problem as 400/1.09728 and that gives us 364.538.

Looking For More to Learn?

Converting ft/s to mph doesn't have to be challenging or complex. All you have to do is multiply feet per second by 1.46666667 or multiply by 0.6818. You can also use a conversion calculator or chart to make the process go faster. 

If you want to learn more simple things to impress your friends and family, then check out our site and discover fun new skills. 


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