An infinitely-long conductor has a current of 14A flowing as shown in the figure. Find the magnetic field at center C.
An infinitely-long conductor has a current of 14A flowing as shown in the figure. Find the magnetic field at center C.
- \(88\mu T\)
- \(44\mu T\)
- \(10\mu T\)
- \(120\mu T\)
The Correct Option is B
Solution and Explanation
The correct option is (B): \(44\mu T\)
\(B=\frac{\mu_0i}{4R}\)
\(=\frac{4\pi\times10^{-7}\times14}{4\times0.1}\)T
\(=\frac{22}{7}\times10^{-7}\times\times140\) T
\(=44\mu\)T
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Concepts Used:
Magnetic Field
The magnetic field is a field created by moving electric charges. It is a force field that exerts a force on materials such as iron when they are placed in its vicinity. Magnetic fields do not require a medium to propagate; they can even propagate in a vacuum. Magnetic field also referred to as a vector field, describes the magnetic influence on moving electric charges, magnetic materials, and electric currents.
A magnetic field can be presented in two ways.
- Magnetic Field Vector: The magnetic field is described mathematically as a vector field. This vector field can be plotted directly as a set of many vectors drawn on a grid. Each vector points in the direction that a compass would point and has length dependent on the strength of the magnetic force.
- Magnetic Field Lines: An alternative way to represent the information contained within a vector field is with the use of field lines. Here we dispense with the grid pattern and connect the vectors with smooth lines.
Properties of Magnetic Field Lines
- Magnetic field lines never cross each other
- The density of the field lines indicates the strength of the field
- Magnetic field lines always make closed-loops
- Magnetic field lines always emerge or start from the north pole and terminate at the south pole.