ASVAB General Science Practice Test 605524

Questions 5
Topics Atom, Atomic Mass, Endoskeleton, Magnetism, Mesosphere

Study Guide

Atom

An atom is the smallest component of an element that still retains the properties of the element.

Atomic Mass

The atomic mass of an element listed in the Periodic Table represents the average mass of a single atom of that element and is measured in atomic mass units (amu). This number is an average as some elements have isotopes with atoms that vary in their number of neturons and, therefore, differ in weight.

Endoskeleton

An endoskeleton (internal skeleton) is a charateristic of vertebrate animals, including humans.

Magnetism

Simple magnets have two poles, north and south, and opposite poles attract each other (N attracts S, S attracts N). Likewise, the same pole of two magnets repel (N repels N, S repels S). The Earth has a magnetic field and North and South Poles which enables the use of a magnetic compass to determine direction.

Mesosphere

In the mesosphere, temperature again drops as altitude increases until the coldest point in the Earth's atmosphere, the mesopause, is reached where temperatures fall to −225 °F (−143 °C).