Why Can't I Solve This Kepler's Law Problem Correctly?

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The discussion revolves around the application of Kepler's Laws to a specific problem involving the comparison of various orbital characteristics. The user struggles to arrive at the correct answers despite multiple attempts, believing their reasoning is sound. Key points include that a planet closer to a star has a shorter orbital period, equal areas are swept out in equal times, and that average speed varies depending on distance from the star. The user presents several answer combinations but finds them incorrect, seeking clarification on their understanding of the laws. The conversation emphasizes the need for precise application of Kepler's principles to solve the problem accurately.
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For some reason, I just can't seem to get this problem right even though I go through it tons of times and I earnestly believe that my answer is correct, but I guess not.

http://img.photobucket.com/albums/v45/takomastock/640ddd43.jpg"

"Use Kepler's Laws to determine the comparison between various items shown in the figure. Assume the figure is drawn to scale.
(Select G-Greater than, L-Less than, E-Equal to, If the first is G and the rest E, enter GEEEE)."

A) A planet with half the average distance to the star would have ... half the period.
B) If area 1 and 3 are equal the time to go from D to E is ... the time to go from A to B
C) The speed at A ... the speed at D
D) The planets's average speed between D and E is ... the average speed between A and B
E) Time to go from B to C is ... time from A to B

I've come up with all these answers and all are wrong. I even narrowed it down to believe that the last 4 answers are "EGLE", but it seems it's wrong.

These are all the possibilities I've come up with, and nope. Still incorrect.

EEGEG

LEGEG

EEGLG

EEGLE

LEGLE

GEGLE

GEGLG

--

Please freaking enlighten me. :cry:
 
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takoma said:
For some reason, I just can't seem to get this problem right even though I go through it tons of times and I earnestly believe that my answer is correct, but I guess not.

http://img.photobucket.com/albums/v45/takomastock/640ddd43.jpg"

"Use Kepler's Laws to determine the comparison between various items shown in the figure. Assume the figure is drawn to scale.
(Select G-Greater than, L-Less than, E-Equal to, If the first is G and the rest E, enter GEEEE)."

A) A planet with half the average distance to the star would have ... half the period.
B) If area 1 and 3 are equal the time to go from D to E is ... the time to go from A to B
C) The speed at A ... the speed at D
D) The planets's average speed between D and E is ... the average speed between A and B
E) Time to go from B to C is ... time from A to B

I've come up with all these answers and all are wrong. I even narrowed it down to believe that the last 4 answers are "EGLE", but it seems it's wrong.

These are all the possibilities I've come up with, and nope. Still incorrect.

EEGEG

LEGEG

EEGLG

EEGLE

LEGLE

GEGLE

GEGLG

--

Please freaking enlighten me. :cry:

1) T^2 = a^3 so as the semimajor axis is cut in half...the period moves down faster than half (L)
B) they must be the same because equal areas are swept out during equal times. (E)
C) (G) seems you understand this
D) Look at the distance traveled in the same period of time...also, when an orbiting object is closer, its average speed is increased(L)
E) the object's speed slows down as it moves away(G)

I believe this is correct...please correct me if I'm wrong
 
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