1. SPEED!

2. CALCULATING SPEED
Speed = Distance traveled Or s = d
Time elapsed t
• Example: If a runner travels 100 m in 10 seconds what was his average speed?
• So, what are the units for speed?
• How would you re-arrange this formula to solve for…
• Distance?
• Time?

3. CONSTANT SPEED
• A moving object that doesn’t change it’s speed travels at constant
speed
• Constant speed means equal distances are covered in an equal amount of time

4. WHAT TIME KNOW FOR TEST ON FRIDAY
• Measurements: how to read a measurement scale, SI/english units
• SI Units: Must know conversion factors from kilo- to milli-
• Know how to convert numbers between unit prefixes
• Precision & accuracy: how to determine if data is precise or accurate
• Significant figures: Determining the number of significant figures in a given number,
determining sig figs in math operations
• Scientific notation: converting from standard form to scientific notation, scientific
notation to standard form, and math operations for scientific notation
• Factor label method: converting units
• Speed: using the speed equation, graphing speed, converting between speed units
• Algebra of physics: rearranging equations to solve for a variable.

5. WHAT TIME KNOW FOR TEST ON FRIDAY
• What to do:
• Review and re-do homework problems
• Review labs we have done in class
• Re-read class and textbook notes
• See powerpoints from class on website
• Review vocab for this unit

6. EXAMPLE: MEASUREMENTS

7. EXAMPLE: SIGNIFICANT FIGURES
• 0.00404
• 30080
• 30080 + 10.004
• 30080 x 20.0

8. EXAMPLE: CONVERSIONS
• Convert 3.00x10 8 m/s (the speed of light) to mph

9. ALGEBRA OF PHYSICS
• In physics, we will be re-arranging a number of equations in order to isolate a variable on
one side of the equation to solve for an unknown. Let’s freshen up on these skills!
• Rearrange the following equations to solve for x:
a = 3x + b
½ x2 +3 = y
5(x + y) = z
½h=j+½x