Question

which statement describes p waves?
○ they start as surface waves.
○ they travel through liquids.
○ they vibrate from side to side.
○ they move slower than s waves

Explanation:

• P waves (primary waves) are a type of seismic wave. They are longitudinal waves and can travel through solids, liquids, and gases.
• "They start as surface waves" is incorrect as P waves are body waves (start from the focus inside the Earth, not surface waves).
• "They vibrate from side to side" is incorrect; that's the motion of S waves (shear waves), while P waves compress and expand (push - pull motion).
• "They move slower than S waves" is incorrect; P waves are faster than S waves.
• So the correct statement is that they travel through liquids.

Answer:

They travel through liquids.