Question

can a pendulum clock be used in an earth- satellite?

2) It is proposed to move a particle in SHM on a rough horizontal surface y applying an external force along the line of motion. Sketch the graph of the applied force against the position of the particle. Note that the applied force has two values for a given position depending on whether the particles is moving in positive or negative direction.

Answer 1

can a pendulum clock be used in an earth- satellite?

Answer:
A satellite is not outside of the earth's gravitational field... if it was, it would just float into space. In theory, it is actually impossible to escape the earth's gravitational field...everything in the universe acts gravitationally with everything else. once you get far enough away, however, it becomes so small that it is undetectable. I am acting gravitationally to you right now, believe it or not. When you hear people talking about spaceships and saying they have escaped the gravitational field, they just mean they have gotten far enough away for the gravitational force to be so small it can be disregarded.

But anyway, to answer your question, no it wouldn't oscillate..but not because it has escaped the gravitational field, because it is in free fall with the satillite. the satellite doesn't move towards the earth because it is experiencing centripetal acceleration. its like you spinning a coin tied to a string around in a circle. you are constantly pulling the coin towards your hand, but the coin doesn't actually get any closer to your hand. or how the sun's gravity is always acting on the earth, but we don't ever actually collide with the sun.

this is because the object circling the other has an initial velocity.

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