| Front | Absorption/excited state |
| Back | The electrons jump to a higher level by absorbing the right amount of energy to move up. |
| Add Reverse | |
| Picture | |
| Tags |
| Front | Strangeness |
| Back | The number of anti-strange quarks in a hadron - the number of strange quarks. Strange quarks, s have strangeness -1, while their anti-particle, s ̅ has strangeness +1 . Very strange! |
| Add Reverse | |
| Picture | |
| Tags |