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- A question about how to interpret a remark on centrifugal force in a popular science book.
Dear all,
currently I'm reading the Dutch translation of Heino Falcke's "Light in the Darkness: black holes, the universe and us" as a preparation on a course on black hole I'm giving later this year. In part 1 it contains a remark about space telescopes, and the author imagines us to travel with the orbiting telescope. It says in the English translation (from Google books, page number isn't shown there, in the Dutch translation it's page 17)
"In orbit, gravity still has us in its grip but we feel weightless because the centrifugal force and the force of gravity are perfectly balanced."
Am I wrong thinking this passage is confusing? There is only a "balance" between gravity and the centrifugal force because you have to include that fictitious force if you decide riding along with the telescope. That's always the case if you decide to travel with an accelerating object, nothing special about it. It also can't be the common mixing up of centrifugal and centripetal force, because the centripetal force of course isn't "balansed" by gravity as some sort of force equilibrium. The true reason for the orbit is simply because the telescope got the right orbiting velocity and gravity is providing the centripetal force. (I guess the remark about weightlesness is because the orbital speed is too slow to induce any artifical weight, as someone on a merry go around or rotating spaceship would experience). What do you think?
And yes, I know the general attitude about popular science by some members here; I'm just asking whether this remark makes sense.
currently I'm reading the Dutch translation of Heino Falcke's "Light in the Darkness: black holes, the universe and us" as a preparation on a course on black hole I'm giving later this year. In part 1 it contains a remark about space telescopes, and the author imagines us to travel with the orbiting telescope. It says in the English translation (from Google books, page number isn't shown there, in the Dutch translation it's page 17)
"In orbit, gravity still has us in its grip but we feel weightless because the centrifugal force and the force of gravity are perfectly balanced."
Am I wrong thinking this passage is confusing? There is only a "balance" between gravity and the centrifugal force because you have to include that fictitious force if you decide riding along with the telescope. That's always the case if you decide to travel with an accelerating object, nothing special about it. It also can't be the common mixing up of centrifugal and centripetal force, because the centripetal force of course isn't "balansed" by gravity as some sort of force equilibrium. The true reason for the orbit is simply because the telescope got the right orbiting velocity and gravity is providing the centripetal force. (I guess the remark about weightlesness is because the orbital speed is too slow to induce any artifical weight, as someone on a merry go around or rotating spaceship would experience). What do you think?
And yes, I know the general attitude about popular science by some members here; I'm just asking whether this remark makes sense.
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