Unit 1: Scientific Method and Data Analysis Vocabulary

Vocabulary flashcards covering the scientific method, measurement accuracy and precision, significant figures, SI units, temperature scales, and graph analysis.

Scientific Method

A process for understanding nature by observing its behavior and conducting experiments to test ideas, solve problems through logical steps, and test the validity of conclusions.

Observation

Descriptions about the characteristics or behavior of nature (also referred to as data) that often lead scientists to formulate a hypothesis.

Hypothesis

A tentative, testable interpretation or explanation of observations that predicts an outcome, often structured in an "If…, then…" format.

Variable

Any factor in an experiment that can change.

Independent Variable

The specific factor in an experiment that the experimenter chooses to change to observe its effect, plotted on the x-axis.

Dependent Variable

The factor in an experiment that is measured or observed to determine the outcome, plotted on the y-axis.

Controlled Variable

A factor that is kept constant and unchanged throughout an experiment, such as room temperature or air pressure.

Scientific Law

A concise statement that summarizes past observations and predicts future ones, describing what nature does without explaining why.

Scientific Theory

A well-substantiated, experimentally validated model or general explanation that describes why nature exhibits specific characteristics and behaviors.

Qualitative Data

Descriptive observational data gathered using the physical senses (sight, smell, hearing, touch) without numerical values.

Quantitative Data

Observational data consisting of numerical measurements and units.

Inferring

The process of using observations and previous experience to formulate a logical conclusion about what happened.

Predicting

Making a statement about a future event or outcome based on historical data and observed patterns.

Exact Measurement

A measured value with zero uncertainty, obtained either by counting individual items or from defined unit conversions.

Inexact Measurement

A measurement that inherently contains some degree of uncertainty or error.

Accuracy

How close a single measurement or average measurement is to the true value, evaluated using percentage error: $\text{\% error} = \frac{|\text{true value} - \text{average}|}{\text{true value}} \times 100$.

Precision

How close a series of repeated measurements are to each other, evaluated using the range: $\text{range} = \text{highest value} - \text{lowest value}$.

Accuracy and Precision Targets

A conceptual diagram illustrating the four possible combinations of experimental data quality: Not Accurate & Not Precise, Accurate & Not Precise, Not Accurate & Precise, and Accurate & Precise.

Significant Figures

All the known certainty digits in a measurement plus the first estimated (uncertain) digit, reflecting the precision of the measurement device.

Analogue Instrument Uncertainty

The estimated measurement limit for non-digital tools (such as rulers or graduated cylinders), equal to $\pm$ half of the smallest scale division.

Digital Instrument Uncertainty

The precision uncertainty associated with electronic measuring devices, equal to $\pm$ the smallest readable decimal unit.

Scientific Notation

A shorthand method for expressing very large or very small numbers in the form $a \times 10^n$, where $1 \le a < 10$ and $n$ is an integer exponent.

SI Base Units

The standardized metric base units of the International System of Units, including meter ($\text{m}$) for length, kilogram ($\text{kg}$) for mass, second ($\text{s}$) for time, Kelvin ($\text{K}$) for temperature, and mole ($\text{mol}$) for amount of substance.

Kelvin Scale

An absolute temperature scale starting at absolute zero ($0\,\text{K}$) with no negative temperatures, where temperature measures average kinetic energy.

Absolute Zero

The lowest theoretical temperature ($0\,\text{K}$, $-273\,^\circ\text{C}$, or $-459\,^\circ\text{F}$), at which all molecular motion virtually stops.

Best-Fit Line

A continuous line or curve drawn on a scatter plot that represents the overall trend of data points without necessarily connecting every individual point.

Directly Proportional

A relationship between two variables on a graph where an increase in the independent variable causes a corresponding increase in the dependent variable.

Inversely Proportional

A relationship between two variables on a graph where an increase in the independent variable causes a decrease in the dependent variable.

Extrapolation

Estimating an unknown data point by extending a graph line along the same slope beyond the boundaries of the measured data points.

Interpolation

Estimating or predicting an unknown data point located between known, measured data points on a graph.