A charged particle moving with veiocity $4 \times 10^6ms^{-1} $
enters perpendicuiar to a magnetic field $B=2 \, Wbm^{-2}.$
It moves in a circular path of radius 2 cm, then charge
per unit mass is
- $10^2C \, kg^{-1} $
- $10^3C \, kg^{-1} $
- $10^4C \, kg^{-1} $
- $10^8C \, kg^{-1} $
The Correct Option is D
Solution and Explanation
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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.