Different Seasons
We divide the year into seasons by weather patterns. Most of the United States has four se...
Scientists have spent many years trying to figure out earthquakes. Massive slabs of rock, called plates, make up the earth's surface. These plates are always moving and changing. The movement causes energy to build up in the plates. When the energy is released in a weak spot of the mass, vibrations travel through the rocks, causing an earthquake. Some earthquakes are so small, people don't even realize they're happening. Others cause massive damage. Scientists use what's called a Richter scale to rate earthquakes on a scale of 1 to 10. Most people will feel an earthquake rated at five, but it usually does not cause much damage to buildings. An earthquake measured at 7 or higher is extremely dangerous. An earthquake measured at 10 has never been recorded. Earthquakes are still very difficult for scientists to predict because they do not seem to follow any pattern.
We divide the year into seasons by weather patterns. Most of the United States has four se...
Sputnik 1 was the first man-made satellite. A satellite is an object that circles around a...
The refrigerator is the most used appliance in America today. Almost every house has one. ...