Universe: Stars And Galaxies
6th Edition
ISBN: 9781319115098
Author: Roger Freedman, Robert Geller, William J. Kaufmann
Publisher: W. H. Freeman
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Chapter 21, Problem 28Q
To determine
The lifetime of a positive pion.
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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 half‑life, at rest, of a positive pion is 1.80×10−8 s.
With what speed V must a positive pion (an unstable particle) be moving to travel 4.60 m (according to the laboratory frame) before it has a 50% chance of decaying?
V = ?m/s
At what fraction V/c of the speed of light must the pion be moving?
V/c = ?
A supernova explosion of a 1.15 × 1031 kg star produces 2.1 × 1044 J of energy.Randomized Variablesm = 1.15 × 1031 kgE = 2.1 × 1044
Part (a) How many kilograms of mass are converted to energy in the explosion?
Part (b) What is the ratio Δm / m of mass destroyed to the original mass of the star?
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
Ch. 21 - Prob. 11QCh. 21 - Prob. 12QCh. 21 - Prob. 13QCh. 21 - Prob. 14QCh. 21 - Prob. 15QCh. 21 - Prob. 16QCh. 21 - Prob. 17QCh. 21 - Prob. 18QCh. 21 - Prob. 19QCh. 21 - Prob. 20QCh. 21 - Prob. 21QCh. 21 - Prob. 22QCh. 21 - Prob. 23QCh. 21 - Prob. 24QCh. 21 - Prob. 25QCh. 21 - Prob. 26QCh. 21 - Prob. 27QCh. 21 - Prob. 28QCh. 21 - Prob. 29QCh. 21 - Prob. 30QCh. 21 - Prob. 31QCh. 21 - Prob. 32QCh. 21 - Prob. 33QCh. 21 - Prob. 34QCh. 21 - Prob. 35QCh. 21 - Prob. 36QCh. 21 - Prob. 37QCh. 21 - Prob. 38QCh. 21 - Prob. 39QCh. 21 - Prob. 40QCh. 21 - Prob. 41QCh. 21 - Prob. 42QCh. 21 - Prob. 43QCh. 21 - Prob. 44QCh. 21 - Prob. 45QCh. 21 - Prob. 46QCh. 21 - Prob. 47QCh. 21 - Prob. 48QCh. 21 - Prob. 49QCh. 21 - Prob. 50QCh. 21 - Prob. 51QCh. 21 - Prob. 52QCh. 21 - Prob. 53QCh. 21 - Prob. 54QCh. 21 - Prob. 55QCh. 21 - Prob. 56QCh. 21 - Prob. 57QCh. 21 - Prob. 58QCh. 21 - Prob. 59QCh. 21 - Prob. 60QCh. 21 - Prob. 61QCh. 21 - Prob. 62QCh. 21 - Prob. 63QCh. 21 - Prob. 64QCh. 21 - Prob. 65QCh. 21 - Prob. 66QCh. 21 - Prob. 67QCh. 21 - Prob. 68QCh. 21 - Prob. 69QCh. 21 - Prob. 70QCh. 21 - Prob. 71QCh. 21 - Prob. 72QCh. 21 - Prob. 73QCh. 21 - Prob. 74QCh. 21 - Prob. 75Q
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