2/25 Physics update and homework due 3/11

Hi folks,

First off NO CLASS NEXT WEEK!!  It's our spring break.  Enjoy the time off everyone!

This week we dove a bit deeper into the concept of energy and work by taking a look at simple machines.  We did a lab were we observed the relationship between force, distance and work as it applies to pulleys.  

For homework this week,

Read this website, starting on the introduction page and finishing on the terminology page (just keep clicking through).

Answer the following questions regarding the lab we did this week in class.

1.  With the pulleys, how did work out relate to work in?

2. What relationship did force have in regards to distance as you worked with the pulleys?

3. As you increased the number of pulleys, what effect did that have on the effort force? What effect did it have on the effort distance?

4. a. If you were lifting a load that required a force of 10N with one pulley, what effort force would be required?

b. Same question, but now you're using 2 pulleys?

c. How about 10 pulleys?

5. a. If you were lifting that load 1 meter, what would the work in distance be for one pulley?

b. 2 pulleys?

c. 10 pulleys?

These question refer to the reading or the lecture.

6. What is the definition of a simple machine?

7. What are 4 things simple machines do?  (Looking for the list on the second page of the website.)

8. What are 5 features of a simple machine?

9.  Name 6 simple machines.  Give me an example of each one.

10.  What is meant by the term "mechanical advantage"?

11.  When is the mechanical advantage of a slope greater?

12.  When is the mechanical advantage of a wedge greater?

13. When is the mechanical advantage of a screw greater?

14.  When is the mechanical advantage greatest for each of the 3 classes of levers?

15.  I've seen the "wheel and axel" characterized as a kind of a lever.  Can you see why this is true?

16.  How would you describe the pulley set ups you used in the lab using the definitions from this website?

17.  What is meant by input force?

18.  What is meant by output force?

19.  What is meant by "work in"?

20.  What is meant by "work out"?

21.  What meant by "load" when it comes to simple machines?

22.  What is meant by my statement "simple machines do a flippy floppy when it comes to force and distance?

23.  Do simple machines change the amount of work it takes to do a job?   (Feel free to use capital letters and exclamation points here.)