Find the point at which the gravitational force acting on any mass is zero due to the earth and the moon system. (such a point is called neutral point). The mass of the earth is 81 times the mass of the moon and the distance between the earth and the moon is 3,85,000km.

Explanation

To find the point at which the gravitational force acting on any mass is zero due to the Earth and Moon system, we can follow these steps:

### Step 1: Understand the Problem
We need to find a point (let's call it point P) between the Earth and the Moon where the gravitational forces exerted by both bodies on a mass placed at point P are equal in magnitude but opposite in direction.

### Step 2: Define Variables
- Let \( M_m \) be the mass of the Moon.
- Let \( M_e = 81 M_m \) be the mass of the Earth (since the mass of the Earth is 81 times that of the Moon).
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