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Velocity signs. A spaceship is traveling away from Earth toward Planet X. Planet X sends an ambassador ship out to meet them. Take the direction of the spaceship relative to the Earth as positive.
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Velocity signs A spaceship is traveling away from Earth toward Planet X. Planet X sends an ambassador ship out to meet them. Take the direction of the spaceship relative to the Earth as positive. The velocity of the ambassador ship relative to Earth is __; the velocity of the ambassador ship relative to the spaceship is __; the velocity of the spaceship relative to the ambassador ship is __, the velocity of the Earth relative to the ambassador ship is __. • -, -, +, + • +, -, +, - • -, -, -, 0 • -, -, +, 0 • -, +, +, -
Velocity Result Which of the following is not a possible correct answer to a velocity transformation problem? -0.9 c +0.9 c +1.2 c more than one of the above is impossible
PAL A proton is traveling at 0.5c relative to the lab. An antiproton is headed for a head-on collision with it, so that it has a speed of 0.9c relative to the proton. To find the velocity of the antiproton relative to the lab, answer these questions: In a sentence, describe your choice of a positive direction. I chose proton relative to lab as + (ok if you chose differently) If v13= answer, what are 1 and 3? antiproton and lab What, then, is 2? proton What are the values ofv12 and v23? -0.9 c and +0.5 c Use velocity transformation to get your answer. -0.72c Do the size and sign of answer make sense? yes - should be negative (opposite proton rel to lab). should be less than the head-on collision speed of 0.9c and should be less than c