edHelper.com
How Does a Seismograph Work?



How Does a Seismograph Work?

A Short Reader

Reading Level
     edHelper's suggested reading level:   grades 5 to 8
     Flesch-Kincaid grade level:   6.52

Vocabulary
     challenging words:    east-west, seismograph, man-made, record, unit, electronics, horizontal, cause, addition, drum, since, speed, solid, minor, marks, world
     content words:    Geological Survey


Print How Does a Seismograph Work?
     Print How Does a Seismograph Work?  (font options, pick words for additional puzzles, and more)


Quickly Print - PDF format
     Quickly Print: PDF (2 columns per page)

     Quickly Print: PDF (full page)


Quickly Print - HTML format
     Quickly Print: HTML


Proofreading Activity
     Print a proofreading activity


Feedback on How Does a Seismograph Work?
     Leave your feedback on How Does a Seismograph Work?  (use this link if you found an error in the story)



How Does a Seismograph Work?
By Cindy Grigg
  

1     Caption: Seismographs at the U.S. Geological Survey record the north-south horizontal, east-west horizontal, and vertical components of the earthquake that took place in California on October 17, 1989.
 
2     A seismograph is a machine that measures the ground motion in an earthquake. When there is an earthquake, everything that touches the ground shakes. The shaking spreads out from the point where the earthquake happened. The shaking spreads at a constant speed. The shaking gets weaker as the distance from the point of the earthquake increases. Many seismographs are located all over the world. They record the earth's movements. Using measurements from three or more seismographs, scientists can tell where an earthquake was located.
 
3     A seismograph has a pen that is hanging in the air. The pen touches a roll of paper called a drum. When an earthquake happens, the roll of paper shakes. The pen does not. A weight holds the pen still. The marks on the paper show the size of the earthquake. A small motor rolls the drum of paper. This lets the seismograph record what happens as time passes. Someone has to change the paper when it runs out.

Paragraphs 4 to 5:
For the complete story with questions: click here for printable


Copyright © 2009 edHelper