Longitudinal waves cannot travel through –

Solution

Longitudinal waves cannot travel through vacuum because such wave requires a medium such as solid liquid or air to travel through. They cannot travel through vacuum or in space. Longitudinal waves, also known as "l- waves", are waves that have the same direction of vibration as their direction of travel, which means that the movement of the medium is in the same direction as, or the opposite direction to, the motion of the wave.