• Support PF! Buy your school textbooks, materials and every day products Here!

Magnetism, Credit-Card magnetic strips

  • #1
Nnk
5
0

Homework Statement


Experiments carried out on the television show Mythbusters determined that a magnetic field of 1000 gauss is needed to corrupt the information on a credit card's magnetic strip. (They also busted the myth that a credit card can be demagnetized by an electric eel or an eelskin wallet.) Suppose a long, straight wire carries a current of 2.5 A. How close can a credit card be held to this wire without damaging its magnetic strip?

I'm not quite sure how to go about this problem, could anyone please explain it?

Homework Equations


Magnetic field of a solenoid:
upload_2014-12-12_16-59-23.png

Where n=N/L


The Attempt at a Solution


Answer: 5.0µm
 

Answers and Replies

  • #2
BvU
Science Advisor
Homework Helper
2019 Award
13,017
3,008
Hi Nn,

Your relevant equation isn't for a simple straight wire. Look e.g. here

Oh, and: next time use the template as it's intended (I.e. show some work under 3, not the answer from the back of the book) :)
 
  • #3
Nnk
5
0
Hi Nn,

Your relevant equation isn't for a simple straight wire. Look e.g. here

Oh, and: next time use the template as it's intended (I.e. show some work under 3, not the answer from the back of the book) :)
Thanks for pointing that out! I didn't know how to calculate it, so I put the correct answer there for those who could help
 

Related Threads on Magnetism, Credit-Card magnetic strips

  • Last Post
Replies
1
Views
2K
  • Last Post
Replies
11
Views
8K
  • Last Post
Replies
7
Views
1K
  • Last Post
Replies
7
Views
2K
  • Last Post
Replies
2
Views
2K
  • Last Post
Replies
0
Views
1K
  • Last Post
Replies
2
Views
2K
  • Last Post
Replies
2
Views
2K
  • Last Post
Replies
1
Views
2K
  • Last Post
Replies
2
Views
5K
Top