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inertial frame of reference/ space help! (1 Viewer)

thaer

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just a quick question from my textbook, "you are in a spaceship heading, you think, in free motion towards Pluto; however, you are far from any reference point to check your progress. suddenly a comet approaches from behind and overtakes you, heading in the same direction. identify which of the following interpretations of events is correct and any method that could distinguish them:
a) the comet is also travelling towards Pluto but at a higher speed.
b) your spaceship is stationary but the comet is heading towards Pluto
c) the comet is stationary and you are travelling away from Pluto
d) you are both travelling away from Pluto, but you have a higher speed."

im pretty sure a and b sound correct, but i don't think there is a way to distinguish between them. am i right?

thank yooh :spin:
 

Aquawhite

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I believe all four are right because there are no other points of reference. If you see the comet travelling further away from you (and you can't see anything else)... you both could be travelling away from Pluto but you can have the higher velocity as long as both the spaceship and the comet are inertial frames of reference.

If you can't feel the movement of the spaceship and there are no other reference points, then how can you tell the difference.

Interesting question. There is no way to distinguish between any of the scenarios since it doesn't say anything about speeds.
 

thaer

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thank you!

but reading the question again, "a comet approaches you from behind and overtakes you, heading in the same direction."

wouldn't this make c and d wrong?
 

zaxmacks

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just a quick question from my textbook, "you are in a spaceship heading, you think, in free motion towards Pluto; however, you are far from any reference point to check your progress. suddenly a comet approaches from behind and overtakes you, heading in the same direction. identify which of the following interpretations of events is correct and any method that could distinguish them:
a) the comet is also travelling towards Pluto but at a higher speed.
b) your spaceship is stationary but the comet is heading towards Pluto
c) the comet is stationary and you are travelling away from Pluto
d) you are both travelling away from Pluto, but you have a higher speed."

im pretty sure a and b sound correct, but i don't think there is a way to distinguish between them. am i right?

thank yooh :spin:
Well we can eliminate b and c, because you have no reference points to determine if you or the comet is stationary. And I think you can eliminate d because the question states that you 'think' you're travelling towards Pluto. So I would say the answer is a.
 

thaer

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Well we can eliminate b and c, because you have no reference points to determine if you or the comet is stationary. And I think you can eliminate d because the question states that you 'think' you're travelling towards Pluto. So I would say the answer is a.
thank you :)
 

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