ANS:A -

The unit of gc is the "gravitational constant" or "acceleration due to gravity," commonly denoted by gc​. It is a conversion factor used in the context of dimensional analysis in fluid mechanics and thermodynamics to relate mass or force to a chosen system of units. The value of gc​ depends on the system of units being used. For example, in the International System of Units (SI), gc​ typically has a value of 9.80665 m/s², representing the acceleration due to gravity on the Earth's surface. However, in other unit systems like the British gravitational system (BG), the value of gc​ may differ. It serves to convert between the units of force (such as newtons or pounds-force) and mass (such as kilograms or slugs) in equations where such conversions are necessary.