Why is negative 40 degrees Celsius equal to negative 40 degrees Fahrenheit?

Answer 1

It just happens that the conversion formula from Celsius to Fahrenheit (and vice versa) gives this result. Here is the conversion formula for -40 C to Fahrenheit:

• F = (C x 1.8) + 32
• F = (-40 x 1.8) + 32
• F = -72 + 32
• Fahrenheit = -40°

Answer 2

This is due to the "offset" of the freezing temperature of water in Fahrenheit. Daniel Fahrenheit's scale established a zero point for brine, not water. Water freezes at 32 °F.

All "positive" temperatures for Celsius have a much larger value on the Fahrenheit scale because of the smaller intervals (degrees). But below 32 °F, the equivalent Celsius temperatures have already gone negative (minus). Eventually, the larger Celsius intervals will close the gap, and this happens at -40°. While Fahrenheit has measured 72 degrees of change, Celsius has measured only 40 of its larger "degrees" (1.8 times as large). So the scales intersect. Below -40°, down to absolute zero, the Fahrenheit values are numerically larger than the Celsius values again.

(see the related questions)

Answer 3

It is simply a coincidence.

In order to convert a temperature from Celsius to Fahrenheit, you must multiply it by 9, then divide by 5, then add 32.

Ie; F=((9*C)/5)+32 where F is degrees Fahrenheit and C is degrees Celsius.

By solving this when the temperature is -40 degrees Celsius, you will see that the temperature is also -40 degrees Fahrenheit.

Answer 4

To find out the number at which the temperature scales converge, set the conversions to equal each other.

5/9(x - 32) = 9/5(x + 32)

5x/9 - 160/9 = 9x/5 + 288/9

25x - 800 = 81x + 1440

56x = -2240

x = -40

Answer 5

A graph of y = mX+ b is a straight line. Two different equations in this form will intersect at exactly one point.

Answer 6

That is pure coincidence.