# Boiling Water Temp: Celsius vs. Fahrenheit

• Foehammer
In summary: This means that to convert from C to F, we multiply by 9/5 and add 32, while to convert from F to C, we subtract 32 and multiply by 5/9. In summary, to convert from Celsius to Fahrenheit, multiply by 9/5 and add 32. To convert from Fahrenheit to Celsius, subtract 32 and multiply by 5/9. In this problem, the Fahrenheit thermometer reads 140° after the temperature of boiling water is brought down, meaning the change in temperature is 72°F. When converted to Celsius, this is equal to 40°C, which does not match any of the given choices. This is because the standard conversion formula cannot be used to convert a
Foehammer

## Homework Statement

A Celsius and a Fahrenheit thermometer are dipped in boiling water. The temperature of the water is brought down until the Fahrenheit thermometer reads 140°. So, the fall in temperature registered by Celsius scale is:
30
40
50
80

F=(C*(9/5))+32
C=(F-32)*(5/9)

## The Attempt at a Solution

Boiling water is 212 F. 212-140=72.
Convert 72 F to C and I get 22.223 C.
My answer doesn't match any of the choices.

If F=1.8C+32

Then F1=1.8C1+32
and F2=1.8C2+32

So you change in F, F2-F1= ? (write in terms of the formula and you'll see that the change in F can't be converted to C using the standard formula).

Alternatively, convert everything to C first.

rock.freak667 said:
If F=1.8C+32

Then F1=1.8C1+32
and F2=1.8C2+32

So you change in F, F2-F1= ? (write in terms of the formula and you'll see that the change in F can't be converted to C using the standard formula).

Alternatively, convert everything to C first.

Got it. Thanks a lot!

Foehammer said:

## Homework Statement

A Celsius and a Fahrenheit thermometer are dipped in boiling water. The temperature of the water is brought down until the Fahrenheit thermometer reads 140°. So, the fall in temperature registered by Celsius scale is:
30
40
50
80

F=(C*(9/5))+32
C=(F-32)*(5/9)

## The Attempt at a Solution

Boiling water is 212 F. 212-140=72.
Convert 72 F to C and I get 22.223 C.
My answer doesn't match any of the choices.

The reason '32' appears in these temperature conversion formulas is that in the Celsius scale, water freezes at 0 C, while this occurs at 32 F on the Fahrenheit scale. Between freezing and boiling, there are 180 Fahrenheit degrees and 100 Celsius degrees, so each Celsius degree is 180/100, or 9/5 Fahrenheit degrees.

Based on your calculations, the correct answer would be 40. The fall in temperature registered by the Celsius scale is 40 degrees, which can be found by subtracting the initial temperature of 212 degrees Fahrenheit from the final temperature of 22.223 degrees Celsius. This conversion can also be verified by using the equation C=(F-32)*(5/9), where C is the temperature in Celsius and F is the temperature in Fahrenheit. Therefore, the correct answer is 40.

## 1. What is the difference between Celsius and Fahrenheit?

Celsius and Fahrenheit are two different temperature scales used to measure the temperature of an object. The main difference between the two is the starting point of the scale. On the Celsius scale, the freezing point of water is 0 degrees and the boiling point is 100 degrees, while on the Fahrenheit scale, the freezing point is 32 degrees and the boiling point is 212 degrees.

## 2. Which scale is better for measuring the boiling point of water?

Both Celsius and Fahrenheit scales are equally accurate for measuring the boiling point of water. However, the Celsius scale is more commonly used in scientific measurements as it is based on a more logical and consistent scale.

## 3. Why does water boil at different temperatures in different locations?

The boiling point of water is affected by several factors, such as altitude, air pressure, and impurities in the water. Higher altitudes have lower air pressure, which means that water will boil at a lower temperature. Additionally, impurities in the water can also affect the boiling point.

## 4. What is the boiling point of water in Kelvin?

Kelvin is another temperature scale commonly used in scientific measurements. The boiling point of water in Kelvin is 373.15 K, which is equivalent to 100 degrees Celsius.

## 5. Is it possible for water to boil at a temperature below 100 degrees Celsius?

No, water cannot boil at a temperature below 100 degrees Celsius under normal atmospheric conditions. In order for water to boil, it needs to reach a certain amount of energy, known as the heat of vaporization, which is achieved at 100 degrees Celsius.

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