Which option lists the freezing point of water in Rankine as 491.67?

Which option lists the freezing point of water in Rankine as 491.67?

• A. 491.67
• B. 273.15
• C. 0
• D. 212

Answer: (A)

The key idea is how to express temperatures on the Rankine scale, which is Fahrenheit-based but uses an absolute zero origin. The freezing point of water is 32 °F. Rankine converts by adding 459.67 to the Fahrenheit value, so 32 + 459.67 = 491.67 R. You can also see this by converting 0 °C to Kelvin (273.15 K) and then to Rankine: 273.15 × 9/5 = 491.67 R. So 491.67 is the Rankine value for the freezing point. The other numbers correspond to different scales or points: 273.15 is 0 °C in Kelvin, 0 is absolute zero in Rankine, and 212 is the boiling point in Fahrenheit.

The key idea is how to express temperatures on the Rankine scale, which is Fahrenheit-based but uses an absolute zero origin. The freezing point of water is 32 °F. Rankine converts by adding 459.67 to the Fahrenheit value, so 32 + 459.67 = 491.67 R. You can also see this by converting 0 °C to Kelvin (273.15 K) and then to Rankine: 273.15 × 9/5 = 491.67 R. So 491.67 is the Rankine value for the freezing point. The other numbers correspond to different scales or points: 273.15 is 0 °C in Kelvin, 0 is absolute zero in Rankine, and 212 is the boiling point in Fahrenheit.