Force acting on a moving charged particle in a region of electric and magnetic fields is called

Options

A. Lorentz force
B. Ampere's force
C. Blot-Savart's force
D. Maxwell’s force

Answer

To solve the question, we need to identify the force acting on a moving charged particle in the presence of electric and magnetic fields. Let's break down the solution step by step:

### Step 1: Understand the Forces Acting on a Charged Particle
When a charged particle moves in an electric field and a magnetic field, it experiences two types of forces:
1. **Electric Force (FE)**: This force is due to the electric field and is given by the formula:
\[ F_E = qE \]
where \( q \) is the charge of the particle and \( E \) is the electric field intensity.

2. **Magnetic Force (FM)**: This force is due to the magnetic field and is given by the formula:
\[ F_M = q(\mathbf{v} \times \mathbf{B}) \]
where \( \mathbf{v} \) is the velocity of the charged particle and \( \mathbf{B} \) is the magnetic field.

### Step 2: Combine the Forces
The total force \( \mathbf{F} \) acting on the charged particle is the vector sum of the electric and magnetic forces:
\[ \mathbf{F} = \mathbf{F_E} + \mathbf{F_M} \]
Substituting the expressions for the forces, we have:
\[ \mathbf{F} = q\mathbf{E} + q(\mathbf{v} \times \mathbf{B}) \]
Factoring out \( q \), we get:
\[ \mathbf{F} = q\left(\mathbf{E} + \mathbf{v} \times \mathbf{B}\right) \]

### Step 3: Identify the Name of the Force
The combined force acting on a charged particle in electric and magnetic fields is known as the **Lorentz Force**. Therefore, the answer to the question is:

**The force acting on a moving charged particle in a region of electric and magnetic fields is called the Lorentz Force.**

### Final Answer
The correct option is **Lorentz Force**.

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