Unit 1: Nature of Science. Measurement. Today most scientists, in almost all countries use the International System of Units (SI units) as their system of measurement. Reason 1: helps scientists share and compare their data/ results Reason 2: Another advantage of SI units is all units are based on the number 10; meaning they are easily converted from one unit to another Unit 1: Nature of Science. Measurement. Length: the distance from one point to another Basic SI Unit of length: meter Base unit symbol: m Tool used to measure length: meter stick Unit 1: Nature of Science. Measurement. Volume: The amount of space that matter occupies. VOLUME OF A LIQUID Basic SI Unit of liquid volume: liter Base unit symbol: L Tool used to measure liquid volume: graduated cylinder Unit 1: Nature of Science. Measurement. Volume of REGULARLY SHAPED SOLID OBJECTS Basic SI Unit of solid volume: cubic centimeter Base unit symbol: cm3 Tool used to measure solid volume: meter stick To calculate solid volume: L x W x H Unit 1: Nature of Science. Measurement. Mass: is the amount of matter that something is made of Basic SI Unit of mass: gram Base unit symbol: g Tool used to measure mass: triple beam balance Unit 1: Nature of Science. Measurement. Volume of an Irregularly Shaped Object Basic SI Unit: cubic centimeter Base unit symbol: cm3 Tool used to measure volume of irreg. solid: graduated cylinder Unit 1: Nature of Science. Measurement. Water Displacement method: Volume of liquid after object has been submerged - Original Volume of liquid in grad. Cylinder Answer is volume of irregular solid object (cm3) Dora Example 48 mL -44 mL 4cm3 ***BECAUSE 1mL = 1cm3 Unit 1: Nature of Science. Measurement. Weight: is a measure of the force of gravity on an object Basic SI Unit of weight: Newton Base unit symbol: N Tool used to measure weight: spring scale Unit 1: Nature of Science. Measurement. Mass vs. Weight Mass DOES NOT change with location, weight DOES! Unit 1: Nature of Science. Measurement. Temperature: is a measure of how hot (or cold) something is. Specifically, the measure of average kinetic energy of the particles in the object. Basic SI Unit of temperature: Degrees Celsius Base unit symbol: °C Tool used to measure temperature: thermometer Unit 1: Nature of Science. Measurement. Time: the measure of a passing interval, from one event to another Basic SI Unit of time: second Base unit symbol: s Tool used to measure time: stopwatch Unit 1: Nature of Science. Measurement. Density the amount of “stuff” in a particular space - The density of room temp. water is 1 gram/ cm3 - An object will SINK in water if an objects density is greater than 1 g/cm3. - An object will FLOAT in water if its density is less than 1 g/cm3 it will. - Density = mass volume Unit 1: Nature of Science. Measurement. An objects density does NOT change when it is broken in half! The molecules are still packed in the same way, no matter the size of the sample. D= m/v D= m/v D= m/v D= 60 g/25cm3 D= 120 g/ 50cm3 D= 96 g/ 40cm3 D= 2.4 g/ cm3 D= 2.4 g/ cm 3 D= 2.4 g/ cm3 .