Question

How is it that we hear sounds when they hit our ear drum even though sound travels at the speed of light while light travels faster than the speed of sound?

Answer 1

The speed of sound and the speed of light are indeed different, but our ability to hear sounds is not dependent on the relative speeds of sound and light. Here's a brief explanation:

1. Speed of sound: Sound waves travel through a medium, such as air, at a finite speed. In air at room temperature, sound travels at approximately 343 meters per second (or about 1,235 kilometers per hour). The speed of sound varies depending on the medium through which it travels. For example, sound travels faster in water than in air.

2. Speed of light: Light, on the other hand, travels at a significantly higher speed. In a vacuum, light travels at approximately 299,792 kilometers per second. In comparison to the speed of sound, light travels much faster.

Now, let's address how we hear sounds:

1. Sound wave propagation: When an object or source vibrates, it generates sound waves that travel through the surrounding medium. These waves are compressions and rarefactions of air molecules, forming a series of pressure variations.

2. Ear and hearing mechanism: When sound waves reach our ears, they enter the ear canal and strike the eardrum, also known as the tympanic membrane. The eardrum vibrates in response to the sound wave's pressure variations.

3. Transfer of vibrations: The vibrations from the eardrum are then transferred to the middle ear, which consists of three tiny bones called the ossicles (malleus, incus, and stapes). The ossicles amplify and transmit the vibrations to the inner ear.

4. Cochlea and auditory nerve: In the inner ear, the vibrations are further transformed into electrical signals by the cochlea, a spiral-shaped structure filled with fluid. These electrical signals are then transmitted to the brain through the auditory nerve.

5. Perception of sound: Finally, the brain processes these electrical signals and interprets them as sound, allowing us to perceive and understand the auditory information.

So, while sound and light travel at different speeds, our ability to hear sounds is based on the physical mechanisms of sound wave propagation and the complex auditory system of the human ear, rather than the relative speeds of sound and light.