A ticking clock sounds loud when you put your ear close to it. As you walk away, the ticking gets softer and softer, until you can’t hear the ticking at all.
The ticking you hear is made by the moving parts of the clock. The movement of these parts – the tiny pushes and pulls – makes the air around the clock move. It pushes the air molecules together into sound waves.
The sound waves from the clock spread out in all directions. They move through the air to your ear, and you hear the ticking.
The sound waves are strongest at the point where they are made – close to the vibrating clock. So when you stand next to the clock, the ticking is loud. But as the sound waves spread out through the air, they grow weaker and weaker. So as you move away from the clock, the ticking gets softer.
By the time the sound waves have travelled across the room, the air is hardly moving at all. The pushes and pulls are too tiny for your ears to pick up, so you no longer hear the sound of the ticking clock.
Picture Credit : Google
