The magnetic flux through a loop varies with time as \(Φ= 5t^2 -3t +5\). If the resistance of loop is \(8\) , find the current through it at \(t = 2\) \(s\)
The magnetic flux through a loop varies with time as \(Φ= 5t^2 -3t +5\). If the resistance of loop is \(8\) , find the current through it at \(t = 2\) \(s\)
\(\frac{15}{8} A\)
\(\frac{5}{8} A\)
\(\frac{17}{8} A\)
\(\frac{13}{8} A\)
The Correct Option is C
Solution and Explanation
The Correct Option is (C) : \(\frac{17}{8} A\)
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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.