European traders brought the first slaves from Africa to the new colonies in the 1600s. After arriving in the New World, they were bought by white masters and had to work on large cotton and tobacco farms in the South. They didn’t get any money for their work and living conditions were very bad. The […]
African Americans are citizens of the United States with ancestors who came from Africa. Their forefathers were brought to American colonies as slaves in the 17th and 18th centuries. About 40 million African Americans, 13% of the total population, live in the USA today. In the past, African Americans have been known by many names.
X-rays are high energy waves that are invisible. They are useful because they can pass through many things that normal light cannot. For example, doctors can see inside the human body and security guards at airports can see inside your handbag.