Notice that the last problem has a negative answer. In the Celsius
system, 0 C is the freezing point of pure water; temperatures above
a. 0 [32 32 = 0
freezing are positive values, and temperatures below freezing (below 0
0 x 5/9 = 0;
C) are denoted by negative numbers (numbers with a negative or minus
sign in front). Negative values will be discussed in Lesson 5.
b. 37.8. [100 32 =
68; 68 x
Is an object that has a temperature of 100 C twice as hot as an object
that has a temperature of 50 C?
c. 100 [21232 =180
Is an object that has a temperature of 100 F twice as hot as an object
180 x 5/9 =
that has a temperature of 50 F?
The answer to both of the above questions must be, "No," because we
d. 17.8 [0 32 =
know of temperatures that go below 0 on each scale. But scientists
desired a system of measurement in which the temperature measured
32 x 5/9 =
the heat energy of an object, beginning with no heat energy. They gave
the term "absolute zero" to this temperature. In 1848, William Thomson
(later Baron Kelvin of Largs) introduced the absolute temperature scale
based upon the Celsius scale. In this thermodynamic scale of
temperature, an object with a temperature of zero has no heat energy.
This temperature is referred to a zero kelvin (0 K). The freezing point of
water is 273.15 K and the boiling point of water is 373.15 K. In 1954, the
kelvin scale was adopted as the SI standard.
NOTE: Originally, temperature was denoted in degrees Kelvin ( K), but
was later changed to kelvin (K) without the degree symbol. When
spelled out, kelvin is spelled without the capital letter. The abbreviation
for kelvin remains a capital letter (K).
The temperature at which an object contains no heat energy is
A temperature of absolute zero (0 K) on the Celsius scale is 273.15 C.
On the Fahrenheit scale, absolute zero is 459.67 F.
0 K (zero kelvin)
a. The temperature at which pure water freezes is
b. The temperature at which pure water boils is
c. Of the Fahrenheit, Celsius, and kelvin scales, which has/have no
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