the upper and lower fixed points of thermometer T are 90 and 10 respectively. Determine the temperature on the Kelvin scale when the reading on T is 30°C
A. 25k
B. 298k
C. 80k
D. 303k
E. 293k?
5 years ago
5 years ago
but what does "fixed points" mean?
If it means water boils at 90 and freezes at 10 then
(C,T ) = (100, 90)
(C, T) = (0 , 10)
T = m C + b
90 = m * 100 + b
10 = m * 0 + b so b = 10
90 = 100 m + 10
m = 0.8
so T = .8 C + 10
if T = 30
20 = .8 C
C = 25
so
K = 273 + 25 = 298
I get B
11 months ago
To determine the temperature on the Kelvin scale, we need to convert the Celsius temperature to Kelvin by adding 273.15.
Given that the upper fixed point of the thermometer T is 90°C and the lower fixed point is 10°C, we can determine the range of temperatures that the thermometer measures: 90°C - 10°C = 80°C.
The range of temperatures on the Kelvin scale will be the same, so on the Kelvin scale, the range will be 80K.
Now, to find the temperature on the Kelvin scale when the reading on thermometer T is 30°C, we can set up a proportion:
(30°C - 10°C) / (90°C - 10°C) = x / 80K
Simplifying the equation:
20°C / 80°C = x / 80K
Taking into account that 20°C is equal to 20K (since we're adding 273.15 to get the Kelvin temperature):
20K / 80°C = x / 80K
Now solve for x:
x = (20K / 80°C) * 80K
x = 20K
Therefore, the temperature on the Kelvin scale when the reading on thermometer T is 30°C is 20K.
The correct answer is not listed among the options provided.