What are the forces acting on stars?

Answer 1

The forces acting on stars are gravitational and electromagnetic. Stars have charge and electromagnetic fields and charge generate forces, F=qE + qvxB. The so-called "dark (missing) matter in galaxies" is a manifestation of the electromagnetic forces on stars.

Roughly a star with mass m in the galaxy, is acted on by the galactic magnetic field B. This is similar to the mass spectrometer.

mv^2/r = qvB = qvuI/r = qvzI/cr

Thus v=qzI/mc the velocity of v is independent of the radius and depeds on the charge to mass ration, q/m.

Answer 2

The main forces acting on stars are gravity, nuclear fusion, and radiation pressure. Gravity pulls the star's matter inward, trying to collapse it, while nuclear fusion in the core produces energy that generates an outward pressure, counteracting gravity. Radiation pressure from the photons produced by nuclear fusion also pushes outward, helping to maintain the star's stability.