This is the magnitude of the magnetic field at the specified point.

[dangish]

The toroid shown in the figure has a wire carrying a current I= 7.10 Amperes wrapped around it N= 820 times. The inner radius is R1 23.0 cm and outer radius R2 27.6cm.

Figure:
http://capaserv.physics.mun.ca/msuphysicslib/Graphics/Gtype63/prob01_torus.gif


What is the magnitude of the magnetic field along a circle that is halfway between the inner and outer edges of the toroid?

Here is what I tried,

B = u0*I*r*N / (2Pi*R^2)

maybe I have to divide N by the current and replace the N in my equation above by N/I??

Please help

 

[NateD]

.No, you don't need to divide N by the current. The equation you have is correct. The magnitude of the magnetic field along a circle that is halfway between the inner and outer edges of the toroid is given by:B = (μ0 * I * N) / (2π * (R2^2 - R1^2))where μ0 is the permeability of free space (4π x 10-7 T.m/A).Substituting the given values, we get:B = (4π x 10-7 T.m/A * 7.10 A * 820) / (2π * (27.6^2 - 23.0^2))B = 0.077 T