What's the difference between weight and mass and how do I find one from the other?

This is often confusing because in everyday life people might say "how much do you weigh?" to which you might say "60kg", 60 kg is actually your mass and when we talk about weight in this topic we are actually talking about a force, we can see this as weight is given in newtons (N) the unit of force. If you had someone sat on your shoulders you would feel them pushing down on you, the force you are feeling is the persons weight, What is causing this force? That is the person's mass. So, all objects and people have mass, this mass causes a force we call weight.

How do we get from one to the other? We us the equation Weight = Mass x Gravitational field strength. As we can see, the weight of an object depends not only on it's mass but also on the gravitational field strength of the planet it is on. For most planets this is different which means that everyone has a different weight on a different planet, for Earth it is 10 N/kg but for the moon is 2 N/kg. So let's say we have a man who's mass is 60kg. We can use the equation to work out his weight on Earth and the Moon. (do calculation) So we see the man weighs 600 N on Earth, and 120 N on the Moon. The important thing to note here is that the man's mass stays the same whatever planet he is on. But his weight will change due to the change in gravitational field strengths.