F = mg

This is just a reinforcement that:

WEIGHT is the FORCE on a mass due to a gravitational field.

MASS is how much matter there is in a body

REMEMBER THAT THESE TWO ARE DIFFERENT!

Other than that, you can use the equation:

(1)
\begin{equation} F = mg \end{equation}

To figure out the weight of masses on other planets or places with a different gravitational acceleration.

e.g.

  • Say you're a lardass and you weigh like $200 kg$s.
  • On Earth, you'd have a weight of:
    • $W = mg$
    • $W = 200 \times 9.8$
    • $W = 1960 N$
  • On the Moon, you'd have a weight of:
    • $W = mg$
    • $W = 200 \times 1.6$
    • $W = 320 N$