For example, a 12.0 kg block of metal has a weight (in N) of N.
But there's nothing special about the Earth—gravitation is a fundamental interaction. This means that any object with mass, regardless of size, will exert a gravitational force on any other object with mass. On the Moon, for example,
g = 1.63 m/s2.
This means an object will weigh about 1⁄6th as much on the Moon as it does on Earth.
Isaac Newton was the first to determine how gravitational forces between objects behave, thus we have Newton's law of universal gravitation,
F =
Gm1m2r2
.
Here, F is the gravitational force,
m1
is the mass of the first particle,
m2
is the mass of the second particle, and r is the distance between the particles. The symbol G (not to be confused with g!) is what's called the universal gravitational constant. As the word "constant" implies, it has the same value everywhere in the universe, for any gravitational force between any objects. Experiments have determined the value of G, in SI units, to be 6.67 ✕ 10−11 N · m2/kg2.