Waves that travel in the rocks below the surface of the earth are called body waves, and there are two types of body waves: primary, or P, waves, and secondary, or S, waves. The S waves, also known as shearing waves, cause the most damage during earthquake shaking, as they move the ground back and forth.arthquake, shaking of the earth's surface caused by rapid movement of the earth's rocky outer layer. Earthquakes occur when energy stored within the earth, usually in the form of strain in rocks, suddenly releases.
Confidence votes 198. You technicaly become a teenager at age 13, because it ends with teen, but puberty begins around 10 if you are going by when they hit puberty. Was this answer useful? Bekah213.
Increased Growth Needs for Teens. Teens grow at astounding rates! Teenage girls grow approximately 23 to 28 cm during their teen years, and teen boys add approximately 26 to 28 cm to their height. Growth during the teen years accounts for about 20% of total height. Not only do teens grow up, but they grow out as well. Weight gain during the teens accounts for about 50% of a personâs ideal adult body weight. Lean body mass (muscle mass, bones, organs â everything except body fat) increases in both teen boys and girls.