UPSC Civil Services Model Paper 6

Primary Waves:
Primary waves (P-waves) are compressional waves that are longitudinal in nature. Hence, Statement 1 is incorrect.
P waves are pressure waves that travel faster than other waves through the earth to arrive at a seismograph.
These waves can travel through any type of material, including fluids as well as solid.
They travel faster than S-waves.
Secondary Waves:
Secondary waves (S-waves) are shear waves that are transverse in nature. Hence, Statement 2 is incorrect.
S-waves can travel only through solids, as fluids (liquids and gases) do not support shear stresses.
S-waves are slower than P-waves.