Video Notes Review: Measurement, Density, Accuracy & Precision

Vocabulary flashcards covering mass, volume, density, measurement methods, accuracy & precision, data collection, and errors.

Mass

A measure of the amount of matter in an object; typically measured with a balance (grams).

Volume

The amount of space an object occupies; measured with devices like a graduated cylinder or ruler.

Density

Mass per unit volume; symbol p; units depend on mass and volume (e.g., g/mL or g/cm^3).

Density formula

p = m / V (density equals mass divided by volume).

Determine density

To determine density, measure mass and volume, then calculate p = m / V.

Mass measurement

Measuring mass with a balance or electronic balance; often requires calibration.

Volume measurement

Measuring volume with a graduated cylinder or appropriate tool; for irregular objects use water displacement.

Density calculation procedure

Use measured mass and volume values in p = m / V; ensure units are consistent.

Accuracy

Closeness of a measured value to the true or accepted value.

Precision

Closeness of repeated measurements to each other (repeatability).

Accuracy vs. precision

Accuracy refers to closeness to the true value; precision refers to reproducibility; ideally both are high.

Systematic errors

Bias that consistently skews measurements in one direction; affects all measurements similarly.

Random errors

Unpredictable fluctuations due to unknown factors; cause scatter in data.

Minimizing measurement errors

Calibrate instruments, avoid parallax, take multiple trials, and record data carefully to reduce errors.