Scientific Units & Conversions Objective: Students will be - - PowerPoint PPT Presentation

Scientific Units & Conversions

Objective: Students will be able to convert units and choose appropriate units of measurement.

Basic S.I. Units

• S.I. Units: Units of measurement that all scientist across the

world agree to use.

• Normally they use the metric system, but there are some

exceptions (i.e. Temperature is Celsius in the metric system but is Kelvin in S.I. units.

Students will be able to convert units and chose appropriate units of measurement. I will be able to use dimensional analysis to convert a metric unit.

Basic S.I. Units

• Important Metric Prefixes

Students will be able to convert units and chose appropriate units of measurement. I will be able to use dimensional analysis to convert a metric unit.

Measurement Unit Abbreviation of Unit Length Mass Time Weight / Force Speed

Metric Prefixes

• Important Metric Prefixes

Students will be able to convert units and chose appropriate units of measurement. I will be able to use dimensional analysis to convert a metric unit.

Prefix

Prefix Abbreviation.

Conversion Rate Kilo- = 1 Base Unit (like a meter) Centi- = 1 Base Unit Milli- = 1 Base Unit

Dimensional Analysis

• Dimensional Analysis: A way to convert units by using fractions that represent

the conversion ratios.

• Steps for Dimensional Analsys:
• 1. Write the original Value as a Fraction
• 2. Create a new fraction beside the original, place the units on the new fraction to cancel out

the original unit.

• 3. Place the conversion numbers beside the matching unit.
• 4. Repeat steps 2 and 3 until you have converted to the appropriate unit.

Students will be able to convert units and chose appropriate units of measurement. I will be able to use dimensional analysis to convert a metric unit.

Dimensional Analysis Practice

• Sometimes you may have to convert more than one unit at a time. Still follow the

same steps.

• Example: Turning Km/H to m/s.

Students will be able to convert units and chose appropriate units of measurement. I will be able to use dimensional analysis to convert a metric unit.

Dimensional Analysis

Example 1: Convert 86.5 grams to kilograms.

Students will be able to convert units and chose appropriate units of measurement. I will be able to use dimensional analysis to convert a metric unit.

Dimensional Analysis

Example 2: Convert 9.8 cm to m.

Students will be able to convert units and chose appropriate units of measurement. I will be able to use dimensional analysis to convert a metric unit.

Dimensional Analysis

Example 3: Convert 45 km/h to m/s

Students will be able to convert units and chose appropriate units of measurement. I will be able to use dimensional analysis to convert a metric unit.

Dimensional Analysis

Example 4: Convert 1,000,000 seconds into a years.

Students will be able to convert units and chose appropriate units of measurement. I will be able to use dimensional analysis to convert a metric unit.

Scientific Notation

• Scientific Notation: A way to write a number using powers of ten.

Steps to Writing Scientific Notation.

• 1. Create the digit by moving the decimal to create a number that is BEWTEEN 1

and 10.

• 2. Multiply by 10.
• 3. Count the number of places the decimal has moved, a create the exponent for 10.
• 4. Moved Left = Positive, Moved Right = Negative.

Students will be able to convert units and chose appropriate units of measurement. I will be able to use dimensional analysis to convert a metric unit.

Scientific Notation

Changing Sci. Not. back to Standard Notation

• 1. If the exponent is “+”, move the decimal right (make the

number bigger), if “ - ” move the decimal left.

Students will be able to convert units and chose appropriate units of measurement. I will be able to use dimensional analysis to convert a metric unit.

Scientific Notation with a Calculator

• Example: 2.99 x 10 8 will look like ( 2.99 E 8 ) on

the calculator.

• Type: ( 2.99 ) ( 2nd ) (x-1 ) ( 8 )

Scientific Notation Examples

• Example 1:

Write the mass of the Earth in Scientific Notation. 5,973,600,000,000,000,000,000,000 kg

Students will be able to convert units and chose appropriate units of measurement. I will be able to use dimensional analysis to convert a metric unit.

Scientific Notation Examples

• Example 2:
• Write the diameter of a carbon-12 atom in scientific notation.
• 0.0000000000000000000000299 mm

Students will be able to convert units and chose appropriate units of measurement. I will be able to use dimensional analysis to convert a metric unit.

Scientific Notation Examples

• Example 3:

The mass of a proton is only 1.66 × 10-27 kg. Write this number in standard form.

Students will be able to convert units and chose appropriate units of measurement. I will be able to use dimensional analysis to convert a metric unit.

Scientific Notation Examples

• Example 4:
• The distance from the Earth to the Sun is 1.49 x 1011 meters. Using

dimensional analysis, convert this value to kilometers and write it in Standard Notation.

Students will be able to convert units and chose appropriate units of measurement. I will be able to use dimensional analysis to convert a metric unit.

Identifying Parts of an Experiment

• AVID Experiment Vocabulary Note Sheet.
• Guide to Creating an Experiment Note sheet.

Students will be able to convert units and chose appropriate units of measurement. I will be able to use dimensional analysis to convert a metric unit.