The Language of Physics

Chapter 1 Section 3

Mathematics and Physics

• The tools of mathematics is used to analyze and summarize observed phenomena.

• Mathematical relationships among physical quantities can be used to help predict what will happen.

Organizing Data

• Data can be easily organized using tables, charts, and equations.

• Data tables are a convenient way to collect data in an organized manner.

• Graphing data is the best way to show data and patterns that might arise.– Often times an equation can be formed to

describe the relationship between variables in an experiment.

Physics and Equations

• In physics, equations are used to indicate the relationship between two or more variables.

• Variables in physics are used to described quantities in equations, which often come from the English and Greek alphabet.– Δ – Greek letter “Delta” → Change in– θ – Greek letter “Theta” → Angle– λ – Greek letter “Lamda”→ Wave length– Σ – Greek letter “Sigma” → Sum of

Abbreviations For Variables and Units

Quantity Symbol Units Unit Abbreviations

Time t Seconds s

Mass m Kilograms kg

Position Δx or Δy Meters m

Dimensional Analysis

• Dimensional analysis makes use of the fact that dimensions can be treated as algebraic quantities.

• Dimensional analysis can be useful to check for problems in equations and answers.– Example:

Order-of-Magnitude

• Order-of-Magnitude: Estimating large and small numbers to the nearest power of 10.– Only done when precise measurements is not

required.• Examples:– 798 m → 103 m (1000 m)– 10,345 m → 104 m (10,000 m)– 0.0091 s → 10-2 m (0.01 m)

Multiply and Dividing Exponents

• Multiplying Exponents

– Examples:

• Dividing Exponents

– Examples: