Changes

[[Matter]], and therefore everything you see, is made out of 3 different types of substances that [[physicist]]s call particles: [[electron]]s, [[proton]]s and [[neutron]]s.

[[Matter]], and therefore everything seen, is made out of 3 different types of substances that [[physicist]]s call particles: [[electron]]s, [[proton]]s and [[neutron]]s.

These particles have been mysterious for quite some time: although [[physicist]]s knew they existed, they knew very little about them. In [[physics]], you can say you "know" something when, among other proprieties ,you can predict and describe the way it behaves. You know that a [[stone]] will fall if it's not held properly. [[Physicist]]s can describe how it falls and predict exactly where it will touch the [[ground]] using mathematical formulas.

These particles have been mysterious for quite some time: although [[physicist]]s knew they existed, they knew very little about them. In [[physics]], you can say you "know" something when, among other proprieties ,you can predict and describe the way it behaves. You know that a [[stone]] will fall if it's not held properly. [[Physicist]]s can describe how it falls and predict exactly where it will touch the [[ground]] using mathematical formulas.