Hard SR questions?
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From: jt64 on 6 Aug 2006 09:18 Ship (A) travel 0.99c approaching earth. At a distance of 300 000 km as seen from planet (B) inertial frame the ship start a framed TV transmission. The transmission is such that 60 frames will be sent from ship (A) during the distance of 300 000 km relative earths inertial frame. Now my question. 1. How long time will it take to travel to planet using (ship point of view). 2. What is the framerate for the transmission within the ship.(ship point of view) 3. How long will it take until the front of first frame is received at planet.(planet point of view) 4. How long will it take until the ship pass planet.(planet point of view) (*5*) How long was the time span between the first and last frame(planet point of view) JT
From: Sorcerer on 6 Aug 2006 09:20 <jt64(a)tele2.se> wrote in message news:1154870281.617016.89810(a)m79g2000cwm.googlegroups.com... | Ship (A) travel 0.99c approaching earth. | At a distance of 300 000 km as seen from planet (B) inertial frame the | ship start a framed TV transmission. | | The transmission is such that 60 frames will be sent from ship (A) | during the distance of 300 000 km relative earths inertial frame. | | Now my question. Do your own homework. Androcles. | | 1. How long time will it take to travel to planet using (ship point of | view). | 2. What is the framerate for the transmission within the ship.(ship | point of view) | 3. How long will it take until the front of first frame is received at | planet.(planet point of view) | 4. How long will it take until the ship pass planet.(planet point of | view) | (*5*) How long was the time span between the first and last | frame(planet point of view) | | JT |
From: jt64 on 6 Aug 2006 09:46 I aready gave the answers in another thread but nobody confirmed they was right. So i changed strategy. JT Sorcerer skrev: > <jt64(a)tele2.se> wrote in message > news:1154870281.617016.89810(a)m79g2000cwm.googlegroups.com... > | Ship (A) travel 0.99c approaching earth. > | At a distance of 300 000 km as seen from planet (B) inertial frame the > | ship start a framed TV transmission. > | > | The transmission is such that 60 frames will be sent from ship (A) > | during the distance of 300 000 km relative earths inertial frame. > | > | Now my question. > > Do your own homework. > Androcles. > > > | > | 1. How long time will it take to travel to planet using (ship point of > | view). > | 2. What is the framerate for the transmission within the ship.(ship > | point of view) > | 3. How long will it take until the front of first frame is received at > | planet.(planet point of view) > | 4. How long will it take until the ship pass planet.(planet point of > | view) > | (*5*) How long was the time span between the first and last > | frame(planet point of view) > | > | JT > |
From: rotchm@gmail.com on 6 Aug 2006 10:00 > Ship (A) travel 0.99c approaching earth. > At a distance of 300 000 km as seen from planet (B) inertial frame the > ship start a framed TV transmission. > > The transmission is such that 60 frames will be sent from ship (A) > during the distance of 300 000 km relative earths inertial frame. Thats all not clear and confusing. Rephrase it all. But I will attempt answer... v=.99c,b=v/c, d=300 000 000m, N=#frames sent out in d. All this is wrt Earth. > Now my question. > > 1. How long time will it take to travel to planet using (ship point of > view). Planet?, you mean earth?: (d/v)*sqrt(1-b2) > 2. What is the framerate for the transmission within the ship.(ship > point of view) Unknown bc you have not specified a frame rate. You only specified a number of frames in d meters, these frames have not been supposed to be done at a constant rate. Did you mean 60 fps? or 1 frame at beginning and 59 frames at end of trip? etc... > 3. How long will it take until the front of first frame is received at > planet.(planet point of view) Again, when was the first frame sent out? > 4. How long will it take until the ship pass planet.(planet point of > view) t=d/v > (*5*) How long was the time span between the first and last > frame(planet point of view) 60 frames in 300 000 000 meters, as posed in the problem, or 60 frames in (d/v) seconds.
From: jt64 on 6 Aug 2006 10:13
rotchm(a)gmail.com skrev: > > Ship (A) travel 0.99c approaching earth. > > At a distance of 300 000 km as seen from planet (B) inertial frame the > > ship start a framed TV transmission. > > > > The transmission is such that 60 frames will be sent from ship (A) > > during the distance of 300 000 km relative earths inertial frame. > > Thats all not clear and confusing. Rephrase it all. But I will attempt > answer... > v=.99c,b=v/c, d=300 000 000m, N=#frames sent out in d. All this is wrt > Earth. > > > > Now my question. > > > > 1. How long time will it take to travel to planet using (ship point of > > view). > > Planet?, you mean earth?: Well earth planet whatever. > (d/v)*sqrt(1-b2) > > > 2. What is the framerate for the transmission within the ship.(ship > > point of view) > > Unknown bc you have not specified a frame rate. You only specified a > number of frames in d meters, these frames have not been supposed to be > done at a constant rate. Did you mean 60 fps? or 1 frame at beginning > and 59 frames at end of trip? etc... I should specified that the transmission was sent at constant rate (most unaccelerated TV are) the rate is such that during the 300 000 km trip to earth the ship release 60 frames. First bits first frame start sending from 300 000 km Last bits of last frame reached earth at 0 km > > > 3. How long will it take until the front of first frame is received at > > planet.(planet point of view) First bits first frame start sending from 300 000 km Last bits of last frame reached earth at 0 km > > 4. How long will it take until the ship pass planet.(planet point of > > view) > > t=d/v > > > (*5*) How long was the time span between the first and last > > frame(planet point of view) > > 60 frames in 300 000 000 meters, as posed in the problem, or 60 > frames in (d/v) seconds. Hmmm really no! read again what i specified above i want to know timespan between the first and last frame reach earth. JT |