INTRODUCTION TO SCIENCE 8 LAWS, THEORIES AND MEASURMENTS

SCIENTIFIC LAWS…… STATEMENT THAT DESCRIBES WHAT SCIENTISTS EXPECT TO HAPPEN EVERY TIME UNDER A PARTICULAR SET OF CONDITIONS CREATED BY NATURE CANNOT BE CHANGED EX. LAW OF GRAVITY

SCIENTIFIC THEORIES…… A WELL-TESTED EXPLANATION FOR A WIDE RANGE OF OBSERVATIONS OR EXPERIMENTAL RESULTS. CREATED BY MAN CAN BE CHANGED, MODIFIED OR DISCARDED EX. ATOMIC THEORY

MEASUREMENT SYSTEM SI - INTERNATIONAL SYSTEM OF UNITS INTRODUCED BY INTERNATIONAL GROUP OF SCIENTISTS TO USE A STANDARD SYSTEM ALLOWS TO COMPARE DATA AND COMMUNICATE WITH EACH OTHER ABOUT THEIR RESULTS.

COMMON SI PREFIXES KILO - K - 1000 HECTO - H - 100 DEKA - DA - 10 DECI - D - 0.1(ONE TENTH) CENTI - C - 0.01(ONE HUNDREDTH) MILLI - M - 0.001(ONE THOUSANDTH)

UNITS OF MEASUREMENT LENGTH - METER - (M) MASS - KILOGRAM - (KG) MASS VS. WEIGHT VOLUME - CUBIC METER (M3) MENISCUS FORMULA FOR VOLUME V=L x W x H DENSITY - MASS PER UNIT VOLUME (KG/M3) FORMULA FOR DENSITY D=M/V TIME - SECOND - S TEMPERATURE - KELVIN - K

SI – International System of Units System of Measurement that allows scientists to compare data and communicate results.

QUALITATIVE…… Do not involve numbers or measurements. Example – noticing a ball is round, or that milk is sour.

QUANTITATIVE…… Observations involving numbers. Example – measuring height or weight.

LENGTH – Meter(m) One meter is about the distance from the floor to the doorknob. What unit would you use to measure long distance? What would you use to measure short distance?

TIME and TEMPERATURE TEMPERATURE – SI Unit is Kelvin. Temperature 0 K is called absolute zero. Nothing can get colder than this temperature and is equal to -273 oC or -459 oF Most use Celsius because water freezes at 0oC and Boils at 100oC TIME – SI Unit is the second. Use clock , watches or digital stopwatches.

WEIGHT VS. MASS WEIGHT – measure of the force of gravity on the object. SI Unit - Newtons Example – your weight on the moon would change and be only 1/6th of what it is on Earth. MASS – amount of matter an object contains. SI Unit - Kilograms Example – your mass does not change whether you are on Earth or the moon

VOLUME Is the amount of space an object takes up. SI Unit – Cubic Meter or m3 Volume of Liquids – Use a graduated cylinder. Meniscus – the curve at the top of the surface of the graduated cylinder.

VOLUME continued… Volume of Rectangular Solids – formula for measuring is Volume = Length x Width x Height Volume of Irregular Solids – Submerge the object in water in a graduated cylinder and the water will rise by the amount that is equal to the volume of the object.

DENSITY Is mass per unit volume. Formula for density is Density=Mass/Volume Does it sink, or float? Objects with a density less than 1 will float Objects with a density greater than 1 will sink