A physics professor on Earth gives an exam to her students who are on a spaceship traveling at speed v relative to Earth. The moment the ship passes the professor, she signals the start of the exam. If she wishes her students to have time T0 (spaceship time) to complete the exam, show that she should wait a time (Earth time) of
before sending a light signal telling them to stop. (Hint: Remember that it takes some time for the second light signal to travel from the professor to the students.)
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Modern Physics
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- Consider the relativistic form of Newtons second law. Show that when F is parallel to v, F=m(1v2c2)3/2dvdt where m is the mass of an object and v is its speed.arrow_forwardIt is said that Einstein, in his teenage years, asked the question, What would I see in a mirror if I carried it in my hands and ran at the speed of light? How would you answer this question?arrow_forwardTwo powerless rockets are on a collision course. The rockets are moving with speeds of 0.800c and 0.600c and are initially 2.52 × 1012 m apart as measured by Liz, an Earth observer, as shown in Figure P1.34. Both rockets are 50.0 m in length as measured by Liz. (a) What are their respective proper lengths? (b) What is the length of each rocket as measured by an observer in the other rocket? (c) According to Liz, how long before the rockets collide? (d) According to rocket 1, how long before they collide? (e) According to rocket 2, how long before they collide? (f) If both rocket crews are capable of total evacuation within 90 min (their own time), will there be any casualties? Figure P1.34arrow_forward
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