Weight is a measurement of the force placed on an object by gravity, whereas mass is the amount of matter an object contains. Mass is commonly denoted using m or M, and weight is denoted with W. More »

Atomic mass is the mass of a single atom or an individual isotope. The atomic weight is the average mass of all naturally occurring isotopes of an element. More »

Molecular mass is expressed as the mass of a molecule in unified atomic mass units, while the number average molecular weight is expressed as the total weight of all molecules in a substance, divided by the overall numbe... More »

Mass is the measurement of how much space an object takes up, and weight is the measurement of the pull of gravity on an object. Scientists measure both mass and weight with the use of balances and scales. The formula we... More »

The mass of an object is the amount of matter it contains while volume is the amount of space it takes up. Mass should not be confused with weight, which is the measure of the gravitational force on an object. More »

Mass is the measurement of the amount of matter that an object contains, while weight represents the gravitational pull on a mass. Physicists calculate the weight of an object by multiplying its mass by the gravitational... More »

Spring scales measure the magnitude of forces, most commonly weight, which is the downward force of gravity on an object. It works from the principle laid down by Isaac Newton in his third law of universal motion, that f... More »