A particle of mass `m` carries an electric positive charge `Q` and is subjected to the combined action of gravity `g` and a uniform horizontal electric field of strength `E`,it is projected with speed `u` to the vertical plane parallel to the electrical field and at an angle `theta `to the horizontal .The maximum distance the particle travels horizontally when it is at the same level as its starting point is

Explanation

To solve the problem of finding the maximum horizontal distance traveled by a charged particle projected in a uniform electric field and under the influence of gravity, we can follow these steps:

### Step 1: Analyze the Motion
The particle is projected with an initial speed \( u \) at an angle \( \theta \) to the horizontal. We can resolve this initial velocity into horizontal and vertical components:
- Horizontal component: \( u_x = u \cos \theta \)
- Vertical component: \( u_y = u \sin \theta \)

### Step 2: Determine the Forces Acting on the Particle
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