Select the word frthe type of seismic waves that arrive at the surface first and move by compressing and expanding the ground like an accordion are called a. s waves. b. p waves. c. surface waves. d. mercalli waves. select the best answer from the choices provided a b c d

Option (B)

Explanation:

Seismic P waves are the primary waves that are generated during an earthquake. This wave propagation can be marked by the alternating compression and extension. The speed of this wave is 4-8 km/sec on average. It can travel at a faster rate, in comparison to the  S waves. So they reach the surface fast. They can travel in both solid as well as liquid. But these waves are less dangerous than the S waves as surface waves propagate through the surface causing a lot of damage.

Thus, the correct answer is option (B).

the motion of a pendulum is a classic example of mechanical energy conservation. a pendulum consists of a mass (known as a bob ) attached by a string to a pivot point. as the pendulum moves it sweeps out a circular arc, moving back and forth in a periodic fashion.