What is the effect on wave speed when medium density increases?

When considering the relationship between wave speed and medium density, an increase in the density of the medium generally leads to a decrease in wave speed for certain types of waves, particularly in solids and fluids. This phenomenon occurs due to the mass per unit volume of the medium affecting how quickly the wave can propagate through it.

In a denser medium, the greater mass means that particles are more closely packed together, resulting in increased inertia. This increased inertia requires more energy to displace the particles and transmit the wave. As a result, the wave is not able to travel as quickly through the denser medium compared to a less dense one, leading to a reduction in wave speed.

It’s worth mentioning that the speed of sound, for example, in gases decreases with an increase in density if temperature is kept constant, as the higher mass requires greater energy input over the same distance. This trend is also observed in some cases for mechanical waves in solids, where increased density can lead to slower propagation speeds due to similar effects on particle movement.

Thus, the correct answer reflects this understanding of wave propagation in relation to medium density.