Question

what are the tiny tiny particles seen in light coming through a hole in a dark room

Answer 1

This happens due to the scattering phenomenon of light by dust particles. Light travels in a straight line path. This principle is called as the Rectilinear Propagation of light. But some objects, like here the small dust particles can come in the path of light and scatter it. Then the path of light is deviated from its straight line path and, as a result of this the dust particles become visible.

Answer 2

Those are the dust particles in the air.
Dust particle's size is comparable to wavelength of light due to which it disperses light waves and makes itself visible.

Hope this helps..
Mark Brainliest♡♡