# Accuracy: The closeness of a measurement to the true or actual value

## Presentation on theme: "Accuracy: The closeness of a measurement to the true or actual value"— Presentation transcript:

Accuracy: The closeness of a measurement to the true or actual value
Accuracy: The closeness of a measurement to the true or actual value. of what is being measured. BEING RIGHT! Accurate: Your measurement = 30.5 cm Actual length = 30.5

Precision: how SPECIFIC a measurement is
Less Precise More Precise 10 m m m 12 m m m 9 m m m Groups of measurements that are CLOSE in range to each other = more precise More SIG. FIGS. = more precise

Precise instruments; Precise measurements
Most precise (least estimation) Least precise (most estimation)

Precision Which ruler is the most precise?
Which ruler is not accurate?

Precision Precision of calculated answers is limited by the least precise measurement. Ex: 2.5 cm cm = 4.75  4.8 Measurements can be precise, but not accurate if an instrument is not calibrated correctly.

Precision & Significant Figures
Answers cannot be more precise than the least precise information given Examples = 23.72 Answer: 23.7 In + and - : Keep same # of decimal places