What is the measure of the force of gravity on an object?
Force is the vector product of mass and acceleration: F = ma. Weight is a special case of that formula, where you substitute the acceleration of gravity, g, for a. We can thus write: W = mg.1
For instance, if an object has a mass of 10 slugs2, its weight near the surface of the Earth is 10 x 32.2 (ft/s2) = 322 pounds (pound-force). If an object has a mass of10 kilograms, its weight near the surface of the Earth is 10 x 9.8 (m/s2) = 98 newtons. You can calculate the force of gravity on an object (i.e., its weight) by putting it on a scale.