By using the temperature of freezing and boiling for water d

By using the temperature of freezing and boiling for water, develop the conversion formula to convert value from Fahrenheit to Celsius. Repeat for Kelvin to Rankin.

Solution

a) Fahrenheit to Celsius

Boiling temperature of water = 100 deg C = 212 deg F

Freezing temperature of water = 0 deg C = 32 deg F

Now, on y-axis we plot Celsius and on x-axis we plot Fahrenheit. The points will be (212, 100) and (32, 0). Now we just need to find the equation of the line joining these two points.

Equation of line will be C - 100 = (0 - 100) / (32 - 212) *(F - 212)

C - 100 = (5/9)*(F - 212)

C - (5/9)*(100*9/5) = (5/9)*(F - 212)

C = (5/9)*(F - 212 + 100*9/5)

C = (5/9)*(F - 32)

b) Kelvin to Rankine

Boiling temperature of water = 373 K = 672 R

Freezing temperature of water = 273 K = 492 R

Now, on y-axis we plot Rankin and on x-axis we plot Kelvin. The points will be (373, 672) and (273, 492). Now we just need to find the equation of the line joining these two points.

Equation of line will be R - 672 = (492 - 672) / (273 - 373) *(K - 373)

R - 672 = (9/5)*(K - 373)

R = 1.8*K