Use the diagram below to answer the following questions. 40 spheres of equal mass make two rings of 20 spheres each. The ring on the right has a radius twice as large as the ring on the left.
If the position of the spheres approximates two uniformly dense rings, which of the following is the concerning a mass placed at position D?
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When dealing with symmetric arrangements of mass, gravitational forces can cancel out, leading to zero net force at certain points.
The net gravitational force due to the spheres of the larger ring would be zero
The net gravitational force due to the spheres of the smaller ring would be zero
The net gravitational force due to the spheres of both rings would be zero
If the smaller ring were removed, the mass would move towards the centre of the larger ring
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The Correct Option isA
Solution and Explanation
Since the sphere at position D is equidistant from all the spheres in the larger ring, the gravitational forces exerted by all the spheres in the larger ring will cancel out due to symmetry, leading to zero net gravitational force.
