Spherical conducting shell?

  • #1
starving_student
1
0
Consider a thin spherical shell of radius 14.5 cm with a total charge of +39.1 micro coulombs distributed uniformly on its surface. (Take radially outward as the positive direction.)
(b) Find the electric field 39.6 cm from the center of the charge distribution.

Round your answer to three significant figures.

...shouldn't the electric field at this point be given by E = k * (q / r ^ 2), where q is 3.91 x 10 ^ -6 C and r is 0.396 m? Same as a point charge right?
It wants the answer in megaNewtons / Coulomb; I give 2.24 MN/C and it's wrong? Why?

Thanks for any input.
 

Answers and Replies

  • #2
Physics Monkey
Science Advisor
Homework Helper
1,363
34
Your formula for the field is certainly correct since the charge is distributed uniformly on the shell and you're looking outside the shell. The only thing I can see is that in your post you say you used the value q = 3.91*10^-6 C when in fact 39.1 micro coulombs would be q = 39.1*10^-6 C. Maybe this is just a typo, or maybe that's your problem.
 

Suggested for: Spherical conducting shell?

Replies
54
Views
2K
Replies
11
Views
669
  • Last Post
2
Replies
44
Views
1K
Replies
7
Views
279
Replies
10
Views
570
Replies
27
Views
909
  • Last Post
Replies
7
Views
970
Replies
10
Views
392
Replies
19
Views
571
Replies
21
Views
425
Top