Lorentz Force | MCQs

Explanation

Explanation

Explanation

The force on a moving charge in a uniform magnetic field depends on:

• Magnetic flux density (B): The strength of the magnetic field.
• The charge on the particle (q): The amount of charge on the particle.
• The speed of the particle (v): The velocity at which the particle is moving.

The force (F) on a moving charge in a uniform magnetic field is given by the Lorentz force equation: F = q (v x B)

Where x denotes the cross product.

Explanation

The force $F$ acting on a charged particle moving in a magnetic field is given by the Lorentz force equation, which can be expressed as:

$$F = q(mathbf{v} times mathbf{B})$$

Where:

• $\mathrm{<font\; color="\#0000ff"><b>F\; is\; the\; force\; acting\; on\; the\; particle,</b></font>}$
• $q$ is the charge of the particle,
• $mathbf{v}$ is the velocity vector of the particle,
• $\mathbf{B}$ is the magnetic flux density (magnetic field strength) vector.

The cross product $\mathbf{v}\times \mathbf{B}$ indicates that the direction of the force is perpendicular to both the velocity and the magnetic field vectors. Thus, the correct expression for the force is $F=qv\times B$.

Explanation

• Fleming's left-hand rule correlates to current, magnetic field and direction of force on a conductor.
• This rule states that if the thumb, forefinger and middle finger of the left hand are stretched to be perpendicular to each other, and if the forefinger represents the direction of the magnetic field, the middle finger represents the direction of the current, then the thumb represents the direction of force.
  

Explanation