Q: Why do comet tails always point away from the sun instead of trailing behind the comet?


Read this paragraph and choose the correct option from the provided answers:

Figure 29.17 shows a comet with two prominent tails. What most people do not know about the tails is that they always point away from the Sun rather than trailing behind the comet (like the tail of Bo Peep’s sheep). Comet tails are composed of gases and dust evaporated from the body of the comet and ionized gas. The dust particles recoil away from the Sun when photons scatter from them. Evidently, photons carry momentum in the direction of their motion (away from the Sun), and some of this momentum is transferred to dust particles in collisions. Gas atoms and molecules in the blue tail are most affected by other particles of radiation, such as protons and electrons emanating from the Sun, rather than by the momentum of photons.

 Choices:

- dust particles attract

- dust particles evaporate

- dust particles liquify

- dust particles recoil


A:
dust particles recoil