Quality is defined as x = 1 - M. In this relationship, what does M stand for?

Quality is defined as x = 1 - M. In this relationship, what does M stand for?

• A. Moisture content
• B. Mass of liquid
• C. Mass of vapor
• D. Total mass

Answer: (A)

Quality in a saturated mixture is the fraction of the total mass that is in the vapor phase. If M represents the liquid portion of the total mass (the moisture content), then the remaining portion must be the vapor, so the sum of liquid and vapor fractions equals 1: M + x = 1. Rearranging gives x = 1 − M. That makes moisture content the correct interpretation of M in this relationship, since it’s the liquid mass fraction of the mixture. The other options describe actual masses or the total mass, not fractions, so they don’t fit the equation x = 1 − M.

Quality in a saturated mixture is the fraction of the total mass that is in the vapor phase. If M represents the liquid portion of the total mass (the moisture content), then the remaining portion must be the vapor, so the sum of liquid and vapor fractions equals 1: M + x = 1. Rearranging gives x = 1 − M. That makes moisture content the correct interpretation of M in this relationship, since it’s the liquid mass fraction of the mixture. The other options describe actual masses or the total mass, not fractions, so they don’t fit the equation x = 1 − M.