When a charged particle moving with velocity is subjected to a magnetic field of induction \(\rightarrow\) B , the force on it is non-zero. This implies that :
- Angle between \(\rightarrow\) B and \(\rightarrow\) V is necessarily 90°
- Angle between \(\rightarrow\) B and \(\rightarrow\) V can have any value other than 90°
- Angle between \(\rightarrow\) B and \(\rightarrow\) V can have any value other than Zero and 180°
- Angle between \(\rightarrow\) B and \(\rightarrow\) V is either Zero 180°
The Correct Option is C
Solution and Explanation
Force on a charged particle moving in a magnetic field is F = q(vB)
So, if v and B are at an angle, F
= qvBsin\(\theta\)
= 0, sin = 0 = 0,180.
Therefore, the correct option is (C): Angle between \(\rightarrow\) B and \(\rightarrow\) V can have any value other than Zero and 180°
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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.