Physics Definitions

1.	Accuracy: is how close a measurement comes to the actual true value of whatever is measured. 
2.	Precision: is concerned with the reproducibility of the results. I.E. how well / close a group of measurements agree with each other. 
3.	Quantitative measurements: give results in a definite form, usually as numbers. Ex. 17 C or 1.3 g of lead. 
4.	Qualitative measurements: give results in a descriptive, nonnumeric form. Ex. This person feels feverish, a bag full of weed, half a glass of beer. 

Rules

1.	Addition + Subtraction

Round up or down to the least number of decimal places from the question. 

Example: 

29.86 + 3.0579 = 32.9179

The smallest number of decimal places is 2, so we would round to 32.92

2.	Multiplication (product) + Division (quotient)

Round final answer to the least number of significant figures according to the question.

Example: 

2.2 X 505 = 1111

The smallest number of sig figs is 2, so we round to 1100.