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Fahrenheit to Celsius Formula

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An Overview of the Conversion Formula for Fahrenheit to Celsius

The terms Fahrenheit and Celsius are the scales that are most often used for reporting room and weather and water temperatures. The Fahrenheit scale is generally used in the United States while the Celsius scale is used worldwide.


In this article, we are going to learn things related to these two scales along with the formulas.


We can say that most of the countries around the world measure their weather and temperatures using the relatively simple Celsius scale. But the country of the United States of America uses Fahrenheit. 


The temperature which is taken as T in degrees Celsius (°C) is equal to the temperature T which is in degrees we see to convert Fahrenheit to celsius = (°F) minus 32 times 5/9:

That is we take T(°C) = (T(°F) - 32) × 5/9

                       or

We can write it as T(°C) = (T(°F) - 32) / (9/5)

                       or

We write it as T(°C) = (T(°F) - 32) / 1.8


For Example

To convert 68 degrees Fahrenheit to degrees Celsius:

We see that \[T_{(^{o}_{C})} = (68^{o}F-32) \times\frac{5}{9} = 20^{o}C\]


Fahrenheit to Celsius Equation

First of all, we need the formula for converting Fahrenheit denoted by letter F to Celsius denoted by letter C:

\[C=\frac{5}{9}(F-32)\]

The notation C represents the temperature in Celsius and the notation F is the temperature in Fahrenheit as discussed earlier.


After we have come across the formula, it is very easy for us to convert Fahrenheit to

Celsius with these three steps that are listed below:

  1. Subtract 32 from the temperature of Fahrenheit.

  2. Then the next is to multiply this number by five.

  3. Then last but not the least divide the result by nine.

For example, suppose the temperature is 80 degrees Fahrenheit and we want to know

what the figure would be in Celsius. So we here use the above three steps that

are as follows:

  1. Example: 80 F – 32 = 48

  2. Then 5 x 48 = 240

  3. And last 240 / 9 = 26.7 C

So the end result is that the temperature in Celsius is 26.7 C. See how easy this is for us to calculate if we remember a few of the steps. If we want to convert a normal human body temperature that is generally 98.6 F, into the Celsius readings, then we need to plug the Fahrenheit temperature into the formula:

\[C=\frac{5}{9} \times (F-32)\]

As we have noted earlier that our starting temperature is 98.6 F. So we would have

the following:

That is \[C=\frac{5}{9} \times (F-32)\]

Then C = 5/9 x (98.6 - 32)

Next we follow C = 5/9 x (66.6)

And C = 37 C

Now we can check our answer to ensure it makes sense. At a temperature which is ordinary a Celsius value is said to be lower always than the corresponding Fahrenheit value. It's helpful to keep in mind that the Celsius scale is based on the boiling and the freezing points of water. The 0 C is the freezing point and 100 C is the boiling point. On the scale of Fahrenheit, water freezes at 32 F and generally boils at 212 F.


Formula to Convert F to C

If we are travelling to a country like Europe for instance and we know the temperature is 74 F, then we might want to know the approximate temperature that too in Celsius. 


Conversion from Fahrenheit to celsius: We need to subtract 30 from the Fahrenheit temperature and then we need to divide by two. So now by using the approximation formula, we can find the following:

That is 74 F – 30 = 44

And 44 / 2 = 22 C.

If we go through the previous formulas which were for calculations of the exact temperature, then we arrive at 23.3.


Conversion of Celsius to Fahrenheit: 

To reverse the approximation process and then convert from 22 C to Fahrenheit, we need to multiply it by two and add 30. So:

We see that 22 C x 2 = 44

And 44 + 30 = 74 C

The first mercury thermometer was invented by the great German scientist Daniel Fahrenheit in 1714. His scale was usually said to divide the freezing and boiling points of water into 180 degrees. That too with 32 degrees as water's freezing point and along with that the 212 as its boiling point.


On the scale of Fahrenheit's scale, zero degrees was determined as the temperature of a temperature-stable brine solution of ice and water and ammonium chloride as well. He based the scale on the temperature which was average of the human body that is which he originally calculated at 100 degrees. So we need to see that it's since been adjusted to 98.6 degrees Fahrenheit.


Convert F to C Formula

The temperature of the Fahrenheit scale is named for German physicist Daniel Gabriel Fahrenheit and it is said as the measurement of temperature commonly used by the United States. On the scale of Fahrenheit, the water freezes at 32°F and usually boils at 212°F that is according to the sea level.


On the scale of  Celsius, water freezes at 0°C and boils at 100°C with respect to the sea level. 


To convert temperatures of these in degrees Fahrenheit to Celsius, we need to subtract 32 and multiply by 0.5556 or we can say 5/9 also.


For Example: (50°F - 32) x 0.5556 = 10°C

We see that to convert C° TO F°: To convert temperatures in degrees Celsius to Fahrenheit, we need to multiply by 1.8 or 9/5 and add 32.


For Example: (30°C x 1.8) + 32 = 86°F

On the scale of Fahrenheit, water freezes at 32 degrees and it boils at a degree of 212. We can say that the freezing and boiling point are therefore 180 degrees apart. So normal body temperature that is usually considered to be 98.6 °F in real life is said to be fluctuating around this value. We can here say that the absolute zero is defined as -459.67°F.


The scale of Celsius is nowadays set in such a way that 0°C is the temperature at which ice freezes and at the other end of the scale, we see 100°C which is the boiling point of water.


Examples of Fahrenheit to Celsius Conversion

1. If the temperature in the USA is 74 °F. What would the temperature be in Celsius?

Solution: To solve this, subtract 32 from the Fahrenheit temperature and multiply it by 5, followed by its division by 9.

74°F-32=42

5x42=210

210/9=23.3

Therefore, the temperature in Celsius would be 23.3 degrees.

To save time, you can subtract 30 from 74 °F. Then divide it by two. So the formulae for it would be:

74 °F-30= 44

44/2= 22°C


2. Convert 36°F to °C using Fahrenheit to Celsius formula.

Solution: Substitute 32 from 36 °F to find the value in Celsius.

°C= (36-32)x5/9

°C= 4x5/9

°C=2.2


3. Convert 108°F to °C.

Solution: Given °F=108

°C=(108-32)x5/9

°C = (76×5)/9

°C = 380/9

°C = 42.2 

Hence, 108°F=42.2°C.


4. Convert 10°F to °C.

Solution: Make use of the formula °C =(°F –32)×5/9

°C=(10-32)x5/9

°C = (-22×5)/9

°C = -110/9

°C = -12.2

Therefore, 10°F= -12.2

FAQs on Fahrenheit to Celsius Formula

1. Explain the formula of Fahrenheit.

The temperature of the Fahrenheit scale is used in every part of the world but mostly used in the USA is the Celsius or the centigrade scale. This scale is employed in most other countries and for scientific purposes worldwide also. The conversion formula which is for a temperature that we have learnt is expressed on the scale of Celsius or we can say °C scale to its Fahrenheit that is °F representation °F = (9/5 × °C) + 32.

2. Explain what is the difference between Celcius and Fahrenheit?

We see that Celsius has 100 degrees which are between the boiling and the freezing point. Whereas we can see that Fahrenheit has 180 degrees which are between these two points. There is one degree Celsius that is 1.8 times larger than one degree Fahrenheit.

3. Explain what is normal body temperature in F?

The average which is of the normal body temperature is generally said to be accepted as 98.6°F that is 37°C. Some studies have shown that the "normal" body temperature can have a wide range which is from 97°F that is 36.1°C to 99°F that is 37.2°C. A temperature that is said to be over 100.4°F that is 38°C most often means you have a fever caused by an infection or we can say illness.

4. Explain which is older Fahrenheit or Celsius?

we can say that Fahrenheit is the standard which is used for measuring temperature in the United States. But on the other hand, most of the rest of the world uses Celsius.  We can say that not too long after the Fahrenheit scale was unveiled, there was a Swedish astronomer Anders Celsius who came out with his temperature scale which is referred to as the Celsius scale.