ASVAB General Science Practice Test 326563

Questions 5
Topics Atomic Number, Chemical Change, Curved Lenses, Fahrenheit Scale, Number System

Study Guide

Atomic Number

The Periodic Table of the Elements categorizes elements primarily by the number of protons in their nucleus (atomic number) and secondarily by the characteristics they exhibit.

Chemical Change

During a chemical reaction molecules and atoms (reactants) are rearranged into new combinations that result in new kinds of atoms or molecules (products).

Curved Lenses

Unlike curved mirrors that operate on the principle of reflection, lenses utilize refraction. A convex lens is thicker in the middle than on the edges and converges light while a concave lens is thicker on the edges than in the middle and diffuses light. A common use for curved lenses is in eye glasses where a convex lens is used to correct farsightedness and a concave lens is used to correct nearsightedness.

Fahrenheit Scale

More familiar in the United States is the Fahrenheit scale in which the freezing point of water is 32°F (0°C) and the boiling point is 212°F (100°C). To convert from C° to F° use the formula:

\(F° = {9 \over 5}C° + 32\)

and to convert from F° to C° use:

\(C° = {5 \over 9} (F° - 32)\)

Number System

The metric system is a number system that designates one base unit for each type of measurement. For example, the base unit for length is the meter and the base unit for mass is the gram.