Microscopic Motion

Forces > Forces and motion > Microscopic Motion 

Particles are in constant motion in nature, but they can have different speeds depending on the internal energy of the system. The internal energy of the system in turn mainly depends on the temperature of the system (the higher the temperature the faster particles move) and the electromagnetic energy between the particles, which tend to bring them together. The average velocity of the molecules of the atmosphere around us is about 1800 km/h. 

Connection to Big Idea about energy: The internal energy of a body (in any state) is the sum of the kinetic energy of its particles (due to their microscopic energy) and the dynamic energy of them (due to the electromagnetic interactions among them).

Connection to Big Idea about the universe: The properties of the light curve and spectra that we receive from the stars is strongly dependent on the microscopic motions of the particles in the photosphere of those stars.

Connection to Big Idea about particles: All particles in nature are observed to have microscopic motions. The lower the temperature the smaller the motions they perform. However, particles can never stand still.

Connection to Big Idea about quantum: Microscopic motions exist at the smallest scales of atoms and subatomic particles. No particle can stay completely still, as Heisenberg’s uncertainty principle forbids it.

Subjects related: Chemistry, Physics

Age ranges: 12-13,14-15,15-16, 17-18