Question

What is ${{19}^{\circ }}F$ in Celsius?

Answer 1

Hint: To convert the temperature from Fahrenheit scale to the Celsius scale we will use the temperature unit conversion formula: $^{\circ }C=\dfrac{5}{9}\left( ^{\circ }F-32 \right)$ and substitute the given value of temperature in $^{\circ }F$ equal to 19. Finally, we will solve for the value of $^{\circ }C$ by simplifying the numerical values in the formula to get the answer.

Complete step by step solution:
Here we are provided with the temperature in Fahrenheit scale as ${{19}^{\circ }}F$ and we are asked to convert it into the Celsius scale. For this temperature conversion we need to see the temperature conversion formula from degree Celsius to degree Fahrenheit or from degree Fahrenheit to degree Celsius.
Now, we know that the unit degree Celsius and degree Fahrenheit are used to measure the temperature of a substance. These units are inter-convertible with the relation: $^{\circ }C=\dfrac{5}{9}\left( ^{\circ }F-32 \right)$ where $^{\circ }C$ denotes the temperature in Celsius and $^{\circ }F$ denotes the temperature in Fahrenheit.
In the above question we have \[^{\circ }F=19\], so substituting this value in the above mentioned formula we get,
$\begin{align}
  & {{\Rightarrow }^{\circ }}C=\dfrac{5}{9}\left( 19-32 \right) \\
 & {{\Rightarrow }^{\circ }}C=\dfrac{5}{9}\left( -13 \right) \\
 & {{\Rightarrow }^{\circ }}C=\dfrac{-65}{9} \\
\end{align}$
Converting the above fraction into decimal we get,
${{\therefore }^{\circ }}C=-7.22$

Hence, ${{19}^{\circ }}F$ is equal to $-{{7.22}^{\circ }}C$.

Note: You must remember the temperature relation between degree Celsius and degree Fahrenheit to solve the above question. If you want you may derive the relation for the value of $^{\circ }F$ for a given value of $^{\circ }C$ whose final outcome is $^{\circ }F={{\dfrac{5}{9}}^{\circ }}C+32$. You must remember the two formulas as it will save time while solving the question. Also remember the relation $K{{=}^{\circ }}C+273$ where K is the S.I unit of temperature known as Kelvin.