The purpose of this experiment is to observe the magnetic field in different geometric conductors: To investigate the spatial distribution of the magnetic field strength between two Helmholtz coils. Aslo we were able to be more familiar with gaussmeter, investigate the existence of magnetic fields generated by electric charge flowing through coils of wire and the way how magnetic field is distributed in these equipments.
A magnetic field is a mathematical description of the magnetic influence of electric currents and magnetic materials. The magnetic field at any given point is specified by both direction and magnitude; as such it is a vector field. We denote the magnetic field with the letter B, and it is measured in tesla. B is most commonly defined in terms of the Lorentz force it exerts on moving electric charges.
A Helmholtz coil is a device for producing a region of nearly uniform magnetic field. It consists of two solenoid electromagnets on the same axis. Besides creating magnetic fields, Helmholtz coils are also used in scientific apparatus to cancel external magnetic fields, such as the Earth’s magnetic field. Formula for magnetic field in Helmholtz coil:
Materials and Procedure
1. DC Current Supply: Creates constant DC current between 0-5 Amps
2. Hall Probe and Gaussmeter: Measures the strength of magnetic field B at the desired position.
3. Helmholtz coils
1. Spatial Distribution of Helmholtz Coils’ Magnetic Field
Firstly, we connect the DC Current supply to the Helmholtz coils in series. We place the coils at a distance equal to the coil radius. We take data in order to demonstrate the change of magnetic field strength with respect to the position of the probe. In the center, we found the maximum value of the magnetic field.
Discussion and Results
1st experiment: Spatial distribution of Helmholtz Coils’ Magnetic field
We will be using this formula:
The magnetic field in the Helmholtz coils definitely is higher at the center and decreases towards one of the ends. Therefore, the magnetic field is highest at the center in between the two coils and the total magnetic field is the sum of the magnetic field from each of the coils. Therefore, it can be inferred that the Helmholtz coils has a uniform magnetic field between them.
We can notice some errors and mistakes done during the experiment that can be as a result of us not taking the correct measurements. Another reason for the errors may be the malfunction of the machines and equipments. Considering all this we still can see from as also from the previous lab that, the graphs that the Magnetic Field formed from the loops at the center is bigger than at the edges of the the Solenoid or the Coils.
Current flowing through a conductor produces a magnetic field. If the conductor is a long straight wire, then the field is distributed over a large region of space. If the wire is used to make a coil, the magnetic field is concentrated into a smaller space and is therefore stronger.
The magnetic field increases with the increase of the turn of coils in three case that we did experiment. In solenoid and Helmholtz coil is present the uniform magnetic field at the center and it is stronger too.
The main reason why it is strong at its center is because that is the place where the magnetic fields formed by different loops join each other and have the greatest value possible.
Knight, R. D., Jones, B., and Field, S. College Physics. 2nd ed. Pearson.
Helmholtz Coils, en.wikipedia.org