Science 1-4 Scientific Tools & Measurement Notes

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**How are observations and measurements related?**

Sometimes observations involve measurements.

A measurement is a description that includes a number or a unit.

 

***Measurements Can Quantify Observations***

Quantitative observations: observations that you make dealing with quantity, like a number or an amount.

Quantitative observations can be made with standardized instruments or approximations and comparisons.

Standardized Instruments:

Rulers**,** Meter sticks**,** Balances**,** Graduated cylinders

Approximations and Comparisons:

Larger, Shorter, Heavy

 

Qualitative observations:  observations you make about characteristics or qualities.

                        Color, Odor, feels like, sounds like

 

**How are measurements expressed?**

            Numbers and units

                        A unit is a standard of measurement and vary depending on measurement system

                        Scientists most often use the International System of Units (SI).

                        ***By Using the International System of Units***

                        Length and Area (meters) - Length: is a measurement of distance.

 

Area: is a measurement of how much surface something has.

 

Volume (liters): a measurement of the amount of space something occupies.

Volume = length x width x height

 

Volume of a solid is usually measured in cubic meters or cubic centimeters.

 

Volume of a liquid is usually measured in liters or milliliters.

 

One milliliter = one cubic centimeter.

 

Mass (grams): a measure of the amount of matter that makes up something.

 

Temperature (Celsius): a measure of how hot or cold something is.

 

***By Using Scientific Notation***

            Is used to express large or small measurements.

            Is a method of writing a quantity as a number multiplied by ten to the power.

 

**What common measurements are made with scientific tools?**

            Graduated Cylinder – used to find volume

            Triple beam balance or an electronic scale – used to find mass

            Stop Watch – used to find how long it takes something to occur

            Thermometer – used to find out how hot or cold something is

            Compass, map, motion detector or GPS – used to measure position

            Spring scale or scale – used to find out how much something weights

            Ruler, meter stick, or GPS – used to find out length

 

**Why is technology important to scientific measurement?**

            Makes it safer, easier, and more accurate.

            Computers alone can store, calculate, and analyze data.

            Computers can also make graphs, spreadsheets, can create models and simulations.

                        ***Technology Makes Difficult Measurements Possible***

                                    Probeware, microscopes, robots and satellites

                        ***Technology Improves Measurements and Saves Time***

New developments improve old technologies and creates new ones that can take better measurements, are more portable and saves time.

 

**How do scientists evaluate tools and measurements?**

            Selecting tools depends if the measurement needs to be exact or close enough.

                        ***By Considering Precision and Accuracy***

Accuracy – compares a measured valued of a property with the standard value accepted for that property.

Precision – an exactness and repeat-ability of a measure.

                        ***With Estimates and Approximations***

                                    Approximations – a number value of limited accuracy.

                                   Estimates – is a rough value representing an actual amount.