If the gravitational force between two objects were proportional to 1/...
Explanation:
In a circular orbit, the centripetal force acting on a particle is provided by the gravitational force between the two objects.
Gravitational force:
According to Newton's law of gravitation, the gravitational force between two objects is given by:
F = G * (m1 * m2) / R^2
where F is the gravitational force, G is the gravitational constant, m1 and m2 are the masses of the two objects, and R is the separation between them.
In this case, the gravitational force is proportional to 1/R instead of 1/R^2. So, the force equation becomes:
F = k * (m1 * m2) / R
where k is a constant of proportionality.
Centripetal force:
In a circular orbit, the centripetal force required to keep the particle in circular motion is given by:
F = (m * v^2) / R
where F is the centripetal force, m is the mass of the particle, v is the orbital speed, and R is the radius of the circular orbit.
Equating the gravitational force and centripetal force:
Setting the gravitational force equal to the centripetal force, we have:
k * (m1 * m2) / R = (m * v^2) / R
Simplifying the equation, we get:
k * (m1 * m2) = m * v^2
Relationship between orbital speed and separation:
From the equation above, we can see that the orbital speed, v, is independent of the separation, R. This means that the orbital speed is constant regardless of the distance between the two objects. Therefore, the orbital speed, v, is proportional to R^0.
Hence, the correct answer is option 'B' - R^0.