Answer :
The magnitude of the rock's acceleration half-way between two planets is 1.086 m/s².
The given parameters;
mass of planet, A = 3M
radius of the planet A, = R
mass of planet B, = 4M
radius of planet B, = 2R
distance between the two planets, r = 8R
The gravitational force half-way (4R) between the two planets is calculated from Newton's universal gravitational law as follows;
SEE IMAGE 1
The magnitude of the rock's acceleration is calculated from Newton's second law of motion as follows;
SEE IMG 2
Thus, the magnitude of the rock's acceleration is 1.086 m/s².
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