Magnetic Field of a Coil Problem

In summary, an observer at point P, midway between two point charges q= +8.00 μc and q'= +3.00μc, is interested in the magnitude and direction of the magnetic field created by the charges. The distance from one charge to the point is .12 m and one charge moves to the right at 4.5 x 10^6 m/s while the other moves to the left at 9.00 x 10^6 m/s. Using the formula B = (μqv X r)/(4∏r^3), where μ is the constant 4∏ x 10^-7 and v X r is the cross product, the magnetic field is calculated to be 4
  • #1
bdh2991
103
0

Homework Statement


a positive point charges q= +8.00 μc and q'= +3.00μc are moving relative to an observer at point p (midway between the charges) the distance from on charge to the point is .12 m and one charge moves to the right at 4.5 x 10^6 m/s while the other moves to the left at 9.00 x 10^6 m/s. when the two charges are at the locations described , what are the magnitude and direction of the magnetic field they produce at point P??




Homework Equations



B = (μqv X r)/(4∏r^3)

where μ is the constant 4∏ x 10^-7, and v X r is the cross product




The Attempt at a Solution



I broke it down into two separate magnetic fields

for the first one I did the cross product of v and r and got 5.4 x 10^6 in the -k direction
then plugged it into the formula and got 2.5 x 10^-6 -k, for the magnetic field

for the second one i did the same thing and with the cross product i got 1.08 x 10^7 -k,
and after plugging that in i got 1.875 x 10^-6 -k

when i added them together i got 4.375 x 10^-6 in the -k direction but the books answer says that the magnetic field is directed into the page...

i never remember using a right-hand rule for these type of problems so am i just supposed to assume that the -k direction is always into the page?
 
Physics news on Phys.org
  • #2
It is conventional for the +k (or +z) direction to equal i×j. This is also known as a "right-handed coordinate system", since the right hand is used to find the direction of i×j.

The result is that, if +x is to the right and +y is up toward the top of the page, then +z is out of the page and -z is into the page. Hope that makes sense for the problem you are working on here.
 

FAQ: Magnetic Field of a Coil Problem

1. What is the magnetic field of a coil problem?

The magnetic field of a coil problem is a physics problem that involves calculating the strength and direction of the magnetic field produced by a coil of wire.

2. How is the magnetic field of a coil calculated?

The magnetic field of a coil is calculated using the formula B = μ0nI, where B is the magnetic field strength, μ0 is the permeability of free space, n is the number of turns in the coil, and I is the current flowing through the coil.

3. What factors affect the magnetic field of a coil?

The strength of the magnetic field of a coil is affected by the number of turns in the coil, the current flowing through the coil, and the permeability of the material surrounding the coil.

4. How does the direction of the magnetic field change in a coil?

The direction of the magnetic field in a coil changes depending on the direction of the current flowing through the coil. The right-hand rule can be used to determine the direction of the magnetic field.

5. What is the purpose of calculating the magnetic field of a coil?

Calculating the magnetic field of a coil is important for understanding and predicting the behavior of electromagnetic systems, such as motors and generators. It is also used in various applications, such as in medical imaging and magnetic levitation technology.

Back
Top