Measurements and Calculations

• Measurement is the quantitative observation. It is a comparison based on an accepted scale. It has two (2) parts- the Number and the Unit.
• Scientific Notation is the technique used to express very large or very small numbers. It is based on powers of 10.
• The name of unit of mass is kilogram.
• The name of unit of length is meter.
• The name of unit of time is second.
• The name of unit of temperature is kelvin.
• mega = M = 10^6
• kilo = k = 10^3
• deci = d = 10^-1
• centi = c = 10^-2
• milli = m = 10^-3
• micro = µ = 10^-6
• nano = n = 10^-9
• The SI unit of length is meter (m). 1 meter is equal to 100 centimeter. 1 cm is equal to 0.01 m which is equal to 10 mm. 1 inch is equal to 2.54 cm.
• Volume is a measure of the amount of three-dimensional space occupied by a substance. The SI unit of length is cubic meter (m^3).
• 1 L = 1000 mL
• 1 mL = 1 cm^3
• Mass is a measure of the amount of matter present in an object. The SI unit of mass is kilogram (kg).
• 1 kg = 2.2046 pounds
• 1 Lb = 453.59 g
• 1 kg = 1000 g
• 1 g = 1000 mg
• 1 g = 0.001 kg
• 1 mg = 0.001 g
• 1 m = 1.094 yd
• 2.54 cm = 1 in
• 1 mi = 5280 ft
• 1 mi = 1760 yd
• 1 kg = 2.205 lb
• 453.6 g = 1 lb
• 1 L = 1.06 qt
• 1 ft^3 = 28.32 L
• The freezing point of Fahrenheit Scale is 32 degrees Fahrenheit. Its boiling point is 212 degrees Fahrenheit.
• The freezing point of Celsius Scale is 0 °C. Its boiling point is 100 °C.
• The freezing point of Kelvin Scale is 273 K. Its boiling point is 373 K.
• To indicate the uncertainty of a single measurement scientists use a system called significant figures. The last digit written in a measurement is the number that is considered to be uncertain. Unless stated otherwise, the uncertainty in the last digit is ±1.
• Nonzero integers are always significant.
• Leading zeros are never significant.
• Captive (embedded) zeros are always significant.
• Trailing zeros are significant if the number has a decimal point.