Question

4)What is meant by vibrations?
5)What is shadow?​

Answer 1

Answer:

4) Vibration, periodic back-and-forth motion of the particles of an elastic body or medium, commonly resulting when almost any physical system is displaced from its equilibrium condition and allowed to respond to the forces that tend to restore equilibrium.

5) The shadow is not a physical thing and it appears faster than light. It is because of that my shadow jumps into bed before I can.