- #1
Gymnos
- 1
- 0
Hi, I'm stuck on a couple problems from my Mastering Physics homework.
#1
There are three space ships (each 10m in length,) each traveling 90m apart from the center spaceship while traveling at a constant speed of .9c. They're entering into an asteroid (215m in length) where some people hope to capture the ships by closing them inside. The locals would like the two ends to close simultaneously in their rest frame, so the front trapdoor will be set to spring .72 microseconds after the first enemy spacecraft passes whereas the rear trapdoor will spring the instant it gets the signal.
How close to the rear of the asteroid will the first enemy spacecraft be when the trapdoors close?
Perhaps L = L[tex]_{0}\sqrt{1-(v/c)^{2}}[/tex] is relevant in this situation.
I tried multiplying .72 microseconds by .9c to get the distance traveled by the first craft during that time, but it returned an incorrect answer of 194. I also tried other combinations, such as adding 10m (in case I hadn't correctly interpreted the wording, and the event activated as soon as the nose of the ship passed the entrance of the asteroid.) That was wrong, too.
For #2
What is the angle [tex]\theta[/tex] that these lines make to the ct axis in the asteroid frame?
I think that's the correct image.
I have no idea how to go about this one, to be honest. I'm not sure if I even understand what the axes represent.
#1
There are three space ships (each 10m in length,) each traveling 90m apart from the center spaceship while traveling at a constant speed of .9c. They're entering into an asteroid (215m in length) where some people hope to capture the ships by closing them inside. The locals would like the two ends to close simultaneously in their rest frame, so the front trapdoor will be set to spring .72 microseconds after the first enemy spacecraft passes whereas the rear trapdoor will spring the instant it gets the signal.
How close to the rear of the asteroid will the first enemy spacecraft be when the trapdoors close?
Perhaps L = L[tex]_{0}\sqrt{1-(v/c)^{2}}[/tex] is relevant in this situation.
I tried multiplying .72 microseconds by .9c to get the distance traveled by the first craft during that time, but it returned an incorrect answer of 194. I also tried other combinations, such as adding 10m (in case I hadn't correctly interpreted the wording, and the event activated as soon as the nose of the ship passed the entrance of the asteroid.) That was wrong, too.
For #2
What is the angle [tex]\theta[/tex] that these lines make to the ct axis in the asteroid frame?
I think that's the correct image.
I have no idea how to go about this one, to be honest. I'm not sure if I even understand what the axes represent.