Maharashtra State PSC Model Paper 4

The correct answer is Both 1 and 2.

Important Point

• Different types of earthquake waves travel in different manners.
• As they move or propagate, they cause vibration in the body of the rocks through which they pass.
• Primary waves (P-waves) vibrate parallel to the direction of the wave.
  • This exerts pressure on the material in the direction of the propagation. As a result, it creates density differences in the material leading to stretching and squeezing of the material. Hence statement 1 is correct.
  • Density difference is created by P-waves.
• The direction of vibrations of secondary waves (S-waves) is perpendicular to the wave direction in the vertical plane, hence they create troughs and crests in the material. Hence statement 2 is correct.