How Physics Starts Your Day
Ring! The alarm clock incessantly chimes to wake its sleeper. You may hate your alarm clock for disturbing your sweet dreams — or you may thank your alarm clock for waking you. But how does physics govern alarm clocks?
The Basics About Waves
Before we dive into the physics behind alarm clocks, let’s understand the basics first.
A wave is a disturbance that transfers energy from one place to another without transferring matter.
There are two type of waves: Mechanical waves and Electromagnetic waves. Mechanical waves (e.g., sound waves) require a medium to travel through, while electromagnetic waves do not.
How does sound travel to your ears
Sound vibrations travel in a wave pattern, and we call these vibrations sound waves. Sound waves move by vibrating objects and these objects vibrate other surrounding objects, carrying the sound along.
As you may know, air is made of particles. The Kinetic Molecular Theory postulates that particles are in a state of constant, random motion.
Air particles surround us and constantly move in random directions. However, with the buzz of an alarm clock, changes to particle movement occur.
The alarm clock vibrates as it rings, which in turn collides with the nearby air particles. The nearby air particles then collide with its surrounding air particles.
Moving air particles collide with further particles, which collide with even further particles. Thus, the disturbance created by the alarm clock’s vibration generates a wave — kinetic energy is transmitted by the collisions.
The wave spreads as the particles transmit vibrations. Finally, the air particles reaches your ear, and the sound is transmitted then interpreted by your brain.
So that’s how physics starts your day! (A good one, I bet.)
