Solve Urgent Magnetic Field Problem - Find Net Field, Charge & Electric Field

In summary: Hi physicsbhelp,I believe that you can find the direction of a magnetic field around a current carrying wire by using the vector sum of the magnetic fields that are present.
  • #1
physicsbhelp
298
0
Urgent Magnetic Field Problem! Urgent!please Help!

1. Homework Statement

a) What is the direction of the net magnetic filed at P due to the currents?
b) Determine the magnitude of the net magnetic field at P due to the currents.


A charged particle at point P that is instantaneously moving with a velocity of 10^6 meters/second toward the top of the page experiences a force of 10^-7 Newtons to the left due to the two currents.

c) State whether the charge on the particle is positive or negative.
d) Determine the magnitude of the charge on the particle.
e) Determine the magnitude and direction of an electric field also at point P that would make the net force on this moving charge equal to 0.



2. The attempt at a solution


I know the answer to part b). it is 6e-6 T and 4e-7 T.

i need help with the other parts. i think, for part a), the direction of the net magnetic field is in the -x becuase the direction of the magnetic filed for the 3Amp wire is +z and the direction of the 1A wire is -z but i need help!



THE PICTURE IS ATTACHED.!.!
 

Attachments

  • Physics Problem.doc
    26 KB · Views: 256
Last edited:
Physics news on Phys.org
  • #2
can't really help until the picture is approved lol. You should jus take a screen shot of the problem and upload the pic to imageshack or something.
 
  • #3
do you know who approves the pictures? can someone please tell them to approve the picture?
 
  • #4
i drew the picture.
so does that mean that no one can see the picture?

well i can give you a general description it is like the x and y-axis but is is slanted, although the angles are 90 degrees.
there is a line going to the x-axis and a line going to the y-axis from point P so basically it looks like a rectangle on top of a almost completely turned x and y-axis. the 3A is on the y-axis and the 1 A is on teh x-axis. the 1.0m line goes from point P to the y-axis and the 0.5m line goes from point P to the x-axis.
 
  • #5
i want to help, but i can't quite understand your description. post it to photobucket and host from there.
 
  • #6
no problem. i think everyone was just waiting for you to post an image, people totally want to help so no don't worry. :)
 
  • #7
HERE IT IS:

http://s139.photobucket.com/albums/q295/dancenyqueen038/?action=view&current=pictureforphysics.jpg

pictureforphysics.jpg
 
  • #8
omg, don't kill me, but i don't get it. i know someone will though.
to verify, the velocity is pointing north, the magnetic Force is pointing left... the magnetic field for the 3Amp wire is +z, and magnetic field for the 1Amp wire is -z...?
 
  • #9
oh, but for part d...
F = q v B sin (theta)
rearrange for q, because you have F and v, and you, yourself found B :)


after you find q, you can do part e...
E = F/q
 
  • #10
wait, what is the value of sin theda? and what is B?
 
  • #11
IS theda 90 degrees?
and i still don't know what B is?
HELP!
 
Last edited:
  • #12
i totally can't even answer you on theta bc the diagram seems to be missing B fields.
B = magnetic field.

all i know is F = 0 when charges move parallel or antiparallel to the magnetic field bc sin0 = 0 and sin180 = 0

i hope someone helps...ill keep checking on this because i want to know the answer too. ps. have you tried posting on answers.yahoo?
 
Last edited:
  • #13
Hi physicsbhelp,

About your answers to part b: they want to know the net magnetic field force that comes from adding the separate magnetic field produced by each wire at point P. Those numbers that you stated, how did you get those? If those were the magnetic fields of the wires then I believe one of them is wrong.
 
  • #14
Hi physicsbhelp,

As I said in my last post, I think a good place to start would be with the two numbers you gave to part b. Did you find them using

[tex]
B = \frac{\mu_0 I}{2 \pi r}
[/tex]

If so, I believe you made a calculation error in one of them. Once you have the correct magnitudes of each magnetic field, you'll then need to find the direction of each which will show you how to add them together. The vector sum of those fields will be the answers to a and b.
 
  • #15
Someone has already given the formula for the magnitude of magnetic field due to an infinite wire carrying a current. Do you know of a method to find the direction of a magnetic field around a current carrying wire?
 

1. What is a magnetic field?

A magnetic field is a region in space where a magnetized object or electrical current experiences a force. It is represented by lines of force that indicate the direction and strength of the field.

2. How do you find the net magnetic field?

To find the net magnetic field, you must first determine the direction and strength of each individual magnetic field. Then, use vector addition to add together the components of each field in order to find the total net field.

3. What is a charge in relation to a magnetic field?

A charge is a fundamental property of matter that determines its electromagnetic interactions. In a magnetic field, charged particles will experience a force that is perpendicular to both the direction of the field and the direction of motion.

4. How do you calculate the electric field in a magnetic field?

The electric field in a magnetic field can be calculated using the equation E = qvB, where q is the charge of the particle, v is the velocity, and B is the magnetic field strength. This equation is known as the Lorentz force law.

5. Why is solving urgent magnetic field problems important?

Solving urgent magnetic field problems is important because magnetic fields play a crucial role in a wide range of applications, including electronics, power generation, medical imaging, and more. Being able to understand and manipulate magnetic fields is essential for technological advancements and scientific research.

Similar threads

  • Introductory Physics Homework Help
Replies
6
Views
282
  • Introductory Physics Homework Help
Replies
14
Views
1K
  • Introductory Physics Homework Help
Replies
7
Views
932
  • Introductory Physics Homework Help
Replies
2
Views
982
  • Introductory Physics Homework Help
Replies
11
Views
1K
  • Introductory Physics Homework Help
Replies
2
Views
306
  • Introductory Physics Homework Help
Replies
25
Views
208
  • Introductory Physics Homework Help
Replies
5
Views
730
  • Introductory Physics Homework Help
Replies
12
Views
2K
  • Introductory Physics Homework Help
Replies
7
Views
139
Back
Top