# 02Post - SUSB-003 BACKGROUND Measuring devices have...

This preview shows pages 1–2. Sign up to view the full content.

1 Introduction to Laboratory Measuremen SUSB-003 Measurement SUSB SUSB-003 003 Last Updated: 9/7/2008 Measuring devices have intrinsic uncertainty i.e., limitations due to their design/construction scale, balance calendar, sundial, watch, USNO measuring cup, graduated cylinder BACKGROUND Uncertainty Measurement process itself may introduce additional uncertainty e.g., try to measure temperature of five drops of a warm solution with a cold laboratory thermometer Measurer usually plays a role in the measurement process reading a scale or liquid level, determining a quantity from a graph, describing the color of a solution BACKGROUND In chemistry, certain quantities are ft n h s n s fund m nt l Measurer/quantities often chosen as fundamental : l ength m ass, t ime (intervals), (area, volume), Many can be described in terms of these, e.g. Temperature Energy ml 2 /t 2 Velocity = l/t ; Electric Currrent; Some cannot, and require other fundamental quantities Many measuring devices are constructed so as to be LINEAR e.g. RULER : Distance between markings is the same everywhere on the ruler ANALOG CLOCK : angle change for 1 minute is the same ( 6 o ) around the entire dial RULE OF THUMB: On a LINEAR SCALE LINEAR SCALE , human eye is capable of estimating the location of a mark lying between two smallest divisions to the nearest 1/5 th of a division Linear/Rule UNITS AND DIMENSIONS What distinguishes scientific computation from arithmetic primarily is that most scientific numbers include units . / Bad news: calculators don’t generally keep calculators don t generally keep track of units. Good news: Proper attention to units by users often shows whether or not a calculation makes sense units PROCEDURE 1. Measure Diameter of Plastic Sphere 2. Weigh Plastic Sphere using two types of balance 3. Compute Density of Sphere using above two results & examine uncertainty 4.

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
This is the end of the preview. Sign up to access the rest of the document.

{[ snackBarMessage ]}

### Page1 / 4

02Post - SUSB-003 BACKGROUND Measuring devices have...

This preview shows document pages 1 - 2. Sign up to view the full document.

View Full Document
Ask a homework question - tutors are online