Universe: Stars And Galaxies
6th Edition
ISBN: 9781319115098
Author: Roger Freedman, Robert Geller, William J. Kaufmann
Publisher: W. H. Freeman
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Question
Chapter 21, Problem 30Q
To determine
(a)
The time taken to travel from Earth to a distant star according to an observer on Earth.
To determine
(b)
The distance to the star from Earth (in light years) according to the observer on Earth and the astronaut.
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Students have asked these similar questions
A star is 12.2 ly (light-years) from Earth.
HINT
(a)
At what constant speed (in m/s) must a spacecraft travel on its journey to the star so that the Earth–star distance measured by an astronaut onboard the spacecraft is 4.36 ly?
m/s
(b)
What is the journey's travel time in years as measured by a person on Earth?
NO SCIENTIFIC NOTATION ANSWERS THANK YOU
Z1 is a star system that is 11.90 light-years away from Earth. Astronauts in an advanced space ship travel from Earth to Z1 at high speed, and they age only 6.50 years during the journey.
(a) How fast were the Astronauts travelling? (b) The ship was launched from Earth by turning trash into 100% energy. How much trash must have been converted into energy to launch the 2.0 x 109 kg ship to this speed?
The cosmic rays of highest energy are protons that have kinetic energy on the order of 1o13 Mev.
(a) As measured in the proton's frame, what time interval would a proton of this energy require to travel across a galaxy which has a proper
diameter 7.80 × 104 ly? (Assume the kinetic energy of the proton is exactly 1013 Mev.)
(b) From the point of view of the proton, how many kilometers across is the galaxy?
km
Chapter 21 Solutions
Universe: Stars And Galaxies
Ch. 21 - Prob. 1QCh. 21 - Prob. 2QCh. 21 - Prob. 3QCh. 21 - Prob. 4QCh. 21 - Prob. 5QCh. 21 - Prob. 6QCh. 21 - Prob. 7QCh. 21 - Prob. 8QCh. 21 - Prob. 9QCh. 21 - Prob. 10Q
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