Find the relation between the gravitational field on the surface of two planets `A` and `B` of masses `m_(A), m_(B)` and radii `R_(A)` and `R_(B), `respectively if
a. they have equal mass.
b. they have equal (uniform)density.

Explanation

To find the relation between the gravitational field on the surface of two planets A and B under the given conditions, we can follow these steps:

### Step 1: Understanding Gravitational Field
The gravitational field \( E \) at the surface of a planet is given by the formula:
\[ E = \frac{G \cdot m}{R^2} \]
where \( G \) is the gravitational constant, \( m \) is the mass of the planet, and \( R \) is the radius of the planet.
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