On microscopic objects:
Newton's law are not valid on the microscopic objects such as electrons, proton, neutron etc. This is because these particles have small masses but large velocities. When they move, they behave as wave.
Objects moving with large velocities:
The Newton's law does not valid on the objects moving with large velocities approaches to the speed of light, because at large velocities the mass of the objects increases.
hyperphysics.phy-astr.gsu.edu
Newton's law are not valid on the microscopic objects such as electrons, proton, neutron etc. This is because these particles have small masses but large velocities. When they move, they behave as wave.
Objects moving with large velocities:
The Newton's law does not valid on the objects moving with large velocities approaches to the speed of light, because at large velocities the mass of the objects increases.
hyperphysics.phy-astr.gsu.edu