There are several different methods, depending on the particular situation. A few that might occasionally be useful include:
-- Read the label on the package.
-- Measure the mass and multiply by the local acceleration of gravity.
-- Measure the mass AND the local acceleration of gravity, then multiply.
-- Place the object or sample on a bathroom scale.
-- Place the object on one end of a symmetrical see-saw. Through trial and error, determine the weight required on the other end to balance the system.
