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?
2 answers
What is 273+30>
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
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