What describes the movement of smoke particles?

The movement of smoke particles is best described as jerky and irregular, which is indicative of Brownian motion. This phenomenon occurs due to the collisions between the smoke particles and the much smaller air molecules surrounding them. These collisions cause the smoke particles to move in a random, zigzag pattern, rather than in a straight line or organized manner. This random movement is characteristic of Brownian motion and illustrates the chaotic nature of particle interactions at the microscopic level.

In contrast, other descriptions such as linear and organized motion or constant speed in a straight line do not accurately represent the unpredictable movement seen in smoke particles. Similarly, the idea of particles being stationary until acted upon does not apply in this context, as smoke particles are consistently in motion due to their interactions with air molecules.