It is commonly known that our Galaxy rotates upon the sun because of gravity. The diagrams' arrows sort of describe it. Id suggest Gravity as the answer.
That would be Protons and Neutrons.
The law of conservation of mass say that, in a chemical reaction, the mass of the reagents will always be equal to the mass of the products. This is shown in the reaction given below.
- Mass of the reagent: 100 g.
- Mass of the products: 56 + 44 = 100 g.
