Gravitational Force: Why is Normal to Path of Satellites, Planets?

AI Thread Summary
Gravitational force acts towards the center of the object being orbited, not necessarily normal to the path unless the orbit is circular. In circular motion, the force is perpendicular to the velocity, resulting in constant speed while maintaining a curved trajectory. The acceleration of an object in circular motion consistently points toward the center, which can be analyzed by separating the x and y components of motion. This analysis shows that the combined acceleration always directs toward the center of the orbit. Understanding these dynamics clarifies why gravitational force influences satellite and planetary orbits.
atlantic
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Why is the gravitational force normal to the path of a satellite, planet etc. ?
 
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hi atlantic :wink:
atlantic said:
Why is the gravitational force normal to the path of a satellite, planet etc. ?

it isn't (unless the orbit is circular), it's towards whatever it's orbiting around :smile:
 
Maybe your question is, why does a force perpendicular to the motion produce a circular orbit? If so, the answer is that an object moving at constant speed in a circle has an acceleration always pointing toward the center of the circle. To see that, analyze the two components of the circular motion (x and y motion) separately, and analyxe the accelerations of the x and y motion separately, and then add the results you got for the acceleration together-- you should see that it always points toward the center.
 

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