There is one long solenoid with turns per unit length. The radius of the solenoid is R and current flowing through it is I. There is a charged particle having charge q and mass m projected from a point on axis of the solenoid, and in a direction perpendicular to the axis. Find the maximum possible speed with which the charged particle can be projected so as not to strike the solenoid.

Explanation

To solve the problem, we need to find the maximum possible speed \( v \) with which a charged particle can be projected from the axis of a solenoid without striking it. Here’s a step-by-step breakdown of the solution:

### Step 1: Understand the setup
We have a long solenoid with:
- Turns per unit length \( n \)
- Radius \( R \)
- Current \( I \)

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