A thin ring of mass M and radius R lies in a plane. At what axial distance x is the gravitational field maximum?
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A thin ring of mass M and radius R lies in a plane. At what axial distance x is the gravitational field maximum?

G1 Physics · Accepted Answer

On the axis, g=GMx/(R²+x²)^(3/2). Setting dg/dx=0 gives R²−2x²=0, hence x=R/√2.