Seismologists and geophysicists often study different types of seismic waves to understand the properties of the Earth's interior. S-waves, or secondary waves, are a type of seismic wave that cannot travel through liquids. Here's why: S-waves are shear waves, which means they cause particles to move in a direction perpendicular to the direction of the wave's propagation**. This movement is possible in solids because the particles in a solid are closely packed together and have a fixed position relative to each other, allowing them to move sideways in response to the shear force. In contrast, liquids do not have this property. The particles in a liquid are not fixed in place and can slide past one another easily. This lack of shear strength means that there is no resistance to the lateral movement that S-waves require to propagate. Since liquids cannot support shear stress, S-waves cannot travel through them. In summary, the key factor that prevents S-waves from traveling through liquids is the absence of shear strength in the medium. read more >>

Why S-waves cannot travel through liquids? S-waves are shear waves, which move particles perpendicularly to their direction of propagation. They can propagate through solid rocks because these rocks have enough shear strength.read more >>