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# If the temperature today is zero degrees and tommorrow the temperature is going to be twice as cold how cold will it be?

#### That would depend on what temperature scale you are using. The scale which places zero degrees at the absolutely coldest point is called the Kelvin scale. It has the same degree divisions as Celsius does. "Absolute zero," or zero kelvins, is the coldest temperature possible. This is the temperature at which all molecules stop all movement. So, if you are measuring in kelvins, twice as cold is not possible. (0/2=0) However, if you are using the Celsius scale, zero degrees is actually 273.15 degrees above absolute zero. So, twice as cold would be -136.575 degrees Celsius. Similarly, absolute zero in Fahrenheit is -459.67. Thus, from zero degrees F, twice as cold would be -229.835 degrees F. Note that, due to the different scales in Celsius and Fahrenheit, just as zero degrees C and zero degrees F are not equal, neither is "twice as cold."

Submitted by Brian (Maryland, USA)
(September 29, 1998)

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