# Homework Help: Some Questions

1. Feb 28, 2008

### j93

[SOLVED] Some Questions

1. The problem statement, all variables and given/known data

http://i244.photobucket.com/albums/gg16/j_93_lkj/prob.jpg

2. Relevant equations
not sure

3. The attempt at a solution
3) I thought answer was 4 because of mg = weight.
17) i thought 1 A/2 * 2L = > R
18) i thought 3) because need parallel circuit to make effective I smaller.
19) not sure how to do
32) not sure
33) I believed it was 2 but it might be 1 because of way + or - are defined
I thought it was C.

Last edited: Feb 29, 2008
2. Mar 1, 2008

### Shooting Star

3. How did you get this 4? mg=weight is correct.

17. R is proportional to length/area. Now figure out the correct choice.

18. In 1, 2 and 3, you are effectively shorting out the cell, and no current will flow through the lamp after S is closed.

19. Since the lamps are in parallel, the PE across them is the same.

32. The value of the elementary charge is the charge of an e- or p+. It can't be divided and must be integral in number. Figure it out.

33. The total will be the sum of the charges. From that, you can calculate which sphere is gaining or losing charge.

3. Mar 1, 2008

### j93

thank you i get how to do them