Physics 1 Problem Solutions 291 - Chapt 38 Special...

Chapt. 38 Special Relativity 287
b) Stirred by your first conquest of space, you and Frodo—well Frodo is less eager—now want
to cross the bulge to the far end of the disk of Galaxy: distance 100 , 000 lyr. But you
want to live to see the journey’s end. What physical effect makes it possible to survive the
journey?
c) How much LESS than the speed of light (in units of c : i.e., in terms of β ) do you need to
go at to make the pan-Galactic journey of 100 , 000 lyr in 1 year for YOU ? HINT: Recall
the first order Taylor expansion
1
√
1 + x
≈ 1 −
1
2
x
which is valid for x<< 1.
d) How long are each of your the trips in dog years for Frodo? And why does Frodo want to
stay at Sirius?
038 qfull 00510 2 5 0 moderate thinking: Frodo and the black hole
6. Once again you and your trusty hound Frodo are voyaging through Galactic space on your star
ship Smaug.
a) Unbeknownst to you, Frodo has an inner life in which he in comtemplates the universe. He