Dimensional analysis for obtaining a quantity in units of Celsius from units of Fahrenheit; one could have started with the equivalence between 100 °C and 212 °F, though this would yield the same formula at the end. Hence, to convert the numerical quantity value of a temperature "T"[F] in degrees Fahrenheit to a numerical quantity value "T"[C] in degrees Celsius, this formula may be used: To convert "T"[C] in degrees Celsius to "T"[F] in degrees Fahrenheit, this formula may be used: Dimensional analysis is most often used in physics and chemistry – and in the mathematics thereof – but finds some applications
Cold inflation pressure volume (assumed to be relatively constant in the case of a tire), and "nR" is constant for a given number of molecules of gas. To understand this, assume the tire was filled when it was 300 kelvins (80 degrees Fahrenheit). If the temperature varies 10% (i.e., by 30 kelvins [also 30 degrees Celsius or 54 degrees Fahrenheit]), the pressure varies 10%. So if the tire was filled at 80 °F to 32 psi (or 47 psi absolute when we add atmospheric pressure), the change would be 4.7 psi for this 30 Celsius degree change, or 0.16 psi per Celsius degree