1. Lessons 12: Choice of Units
Goal: determine appropriate units for various measurements and rewrite measurements based on new units.
Warm Up
Exercises 1-3 for Lesson 12

2. We Do Gigaelectronvolt
Is kilogram the best measure for the mass of a proton?
1 gigaelectronvolt = x kg
Mass of 1 proton = x kg
Convert the mass of a proton from kilograms to gigaelectronvolts.(Exercise 4)

3. 1 gigaelectronvolt = 1.783 x 10-27 kg
Mass of 1 proton = x kg
Let x be the number of gigaelectronvolts equal to the mass of a proton.

4. Light-years (Exercise 5 Lesson 12)
You Try

6. Lessons 12: Choice of Units
Class Work
Lesson 12 Exit Ticket
Homework
Lesson 12 Problem Set #1-3

7. Lesson 13: Comparison of Numbers in Scientific Notation
Comparing Magnitude
Goal: compare numbers expressed in scientific notation.

8. Lesson 13: Comparison of Numbers in Scientific Notation
We Do
Leo I Dwarf How do we know?

9. Lesson 13: Comparison of Numbers in Scientific Notation
You Try
Exercise 1
Fornax Dwarf is closer because a number to the 5th magnitude is smaller than a number to the 6th magnitude.

10. Lesson 13: Comparison of Numbers in Scientific Notation
You Try
Exercise 2
The tau lepton has a longer average lifetime because has a greater magnitude than

11. Lesson 13: Comparison of Numbers in Scientific Notation
Class Work
Lesson 13 Exit Ticket
Homework
Lesson 13 Problem Set #1-3