1. 2016/8/29 Significant figures Scientific notation Dimensional analysis
Physics 111 SI
2016/8/29
Significant figures
Scientific notation
Dimensional analysis

2. Questions?

3. Sessions setup Mondays: Review and preview with PowerPoint outline
Tuesdays: Worksheets and open for in-session questions
Wednesdays: Worksheets and open for in-session questions
Session ppts and answer keys to worksheets won’t be uploaded on PHYS 111 SI website

4. Significant figures
How many significant figures do these numbers have? 1) 2)
3) 2500
If you are solving a question that has 2.7s and 6.23m in the question itself, how many significant figures you need to put in your answer?

5. Significant figures Nonzero digits are always significant
Any zeros between two significant digits are significant
A final zero or trailing zeros in decimal portion are significant

6. Scientific notation Put the prefixes on your “cheat sheet”
Let’s write some numbers into
scientific notation: 1) 2) 4)

7. Dimensional analysis
Trigonometric functions

8. Dimensional analysis
We need to set up a coordinate system before describe any motion
What are the two things to do to set up a coordinate system?
1) Define the origin
2) Define the positive direction

9. Dimensional analysis
What is the difference between vector and scalar quantities?

10. Dimensional analysis
What is the slope in this two types of graphs? 1) Graph of position as a function of time (x vs. t) Slope = velocity 2) Graph of velocity as a function of time (v vs. t) Slope = acceleration

11. Dimensional analysis Do you still remember this question from lecture?
A quick trick for conceptual problems like
this:
Assign actual
values
(e.g.: -3m/s)
according to
the conditions
in the question