Double Conversion Factor Method

This section explains the process of converting units when two conversion factors are needed, using the example of converting speed from kilometers per hour to meters per second.

Example: Converting 72 km/h to m/s requires:

1. Converting kilometers to meters $1000 m = 1 km$
2. Converting hours to seconds $1 h = 3600 s$
3. Final result: 20 m/s

Highlight: When dealing with compound units like speed, each unit must be converted separately using appropriate conversion factors.

Definition: Compound units are measurements that combine two or more different units, such as speed (distance/time) or density (mass/volume).

Vocabulary:

• Compound units: Units that combine two or more basic units
• Speed conversion: The process of changing velocity measurements from one unit to another

Single Conversion Factor Method

This section presents a detailed 12-step process for converting units using a single conversion factor. The methodology is clearly structured to ensure accurate unit conversions.

Definition: A conversion factor is a ratio between two equivalent measurements expressed in different units.

Example: Converting 1200 meters to kilometers follows these key steps:

1. Write initial value (1200 m)
2. Set up conversion factor $1 km/1000 m$
3. Cancel out common units
4. Perform calculation to get 1.2 km

Highlight: The proper placement of units in the numerator and denominator is crucial for successful conversion.

Vocabulary:

• Numerator: The top part of a fraction
• Denominator: The bottom part of a fraction
• Conversion factor: A fraction that equals 1 and shows the relationship between two units