Final answer:
Sound vibrations result from mechanical waves and require a medium to propagate, whereas thermal motion is the random movement of particles due to thermal energy and doesn't require a medium.
When sound transfers between different media, its wavelength changes but the frequency remains constant due to the source remaining the same while the speed varies with the medium. Electromagnetic waves don't need a medium to travel, unlike mechanical waves.
Step-by-step explanation:
To address how sound vibrations of atoms differ from thermal motion, we must understand that they have different origins. Sound vibrations in atoms occur due to the propagation of mechanical waves, which necessitate a physical medium to travel through.
They are pressure disturbances that move through substances such as air or water. Thermal motion, on the other hand, refers to the random movement of particles in a material due to their thermal energy. It is not a wave phenomenon and does not require a medium to occur as it pertains to the internal kinetic energy within a substance.
When sound passes from one medium to another, its speed changes, which leads to a change in wavelength, but the frequency remains constant. This occurs because the frequency of a wave is determined by the source and does not change as the wave enters different media.
However, the speed of sound is dependent on the properties of the medium, and when it changes, the wavelength must adjust to maintain the constant frequency.
No, not all waves require a medium to travel. Electromagnetic waves do not require any medium to propagate; they can travel through vacuum.
On the other hand, mechanical waves, such as sound waves, do require a medium because they involve the oscillation of the particles within that medium.