Isaac newton was the person in the 1600s who drew attention to Gravity, and thus to Mass. Perhaps before then, one only had weight!
You might discover that solids have mass and they have volume.
the mass energy equivalence formula
Bohr did not discover this. Ernest Rutherford 'discovered' the nucleus. This was done in 1911.
The mass spectrometer was used to discover that not all atoms of neon have the same mass. This instrument separates and measures atoms based on their mass-to-charge ratio, allowing scientists to identify isotopes of elements like neon that have different masses.
in 1905
mass production and the assembly line.. Henry Ford did not discover mass production nor did he discover the assembly line. The modern assembly line was patented by Ransom Olds in 1901 at the Olds Motor Vehicle Company 7 years before the Ford Motor Company was founded in 1908. Mass production goes back as far as the Chinese in the 16th century. Henry Ford did not discover or invent anything. He just perfected what was already there.
That most of an atom's mass was packed in a central nucleus
That most of an atom's mass was packed in a central nucleus
Einstein discovered mass and energy relation (e=mc2)
he formulated an early version of the periodic table based on atomic mass
Neutrons were hypothesized by Earnest Rutherford, as a link between atomic number and atomic mass.
Rutherford discovered that almost entire mass of an atom is located in the nucleus, and then, the neutron was discovered by Chadwick.