A sound wave is a wave of compression and rarefaction, by which sound is propagated in an elastic medium such as air.
Answer:
A. The particle model, because only high-energy frequencies of light can remove electrons .
Explanation:
Each photon of blue light has higher energy than each photon of red light has . So when each photon strikes each electron , it gets ejected . But the photon of red light has not sufficient energy to eject electron . Once the photon of red light strikes the electron , the energy is wasted off . Energy of photon can not be accumulated . Thus photon behaves like particle .
The sun?? It stays in one spot, but from our point of view, it travels around the earth...
