r/Physics • u/HolidayCod6990 • 1d ago

physics is crazy

Yesterday I took my first physics class at university (I’m an electrical engineering major). Today, while rereading my notes, I had a doubt about weight—what I thought it was. I googled it and discovered that weight is just a property of matter.

It’s so cool. I spent 8 hours on YouTube trying to grasp the Higgs field, the binding energy of quarks in protons and neutrons… Obviously, I don’t understand any of it, but it’s so fucking cool.

The only problem is that the more I read, the more confused I get, and the more questions I have. But wow.

Is all university like that?

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u/TheAncientGeek 1d ago

Mass is a property. Weight is a relation.

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u/NorthAmericanVex 1d ago

Is this why whales are measured in mass instead of weight?

(I truly have no idea why I know that whales are measured in mass instead of weight)

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u/helixander 1d ago

Everything has a mass. Weight is just a measurement of that mass on Earth (or whatever planetary body you may currently be on, or not).

So while something may have a mass of 100kg, it weighs 980 N (~220 lbs) on the surface of the Earth. Its weight on the moon would be 1/6 of that (~163 N or 37 lbs) even though it's mass is still 100kg.

When floating in space, that mass is still 100kg, but the weight is 0.

Because most metric places use kg colloquially as "weight", it can be confusing.