Answers to Selected Problems - West Valley College

Problem Sets Physics 4D
1) If you were traveling with respect to the stars at a speed close to the speed of light, you could detect it
because
a) your mass would increase
b) your heart would slow down
c) you would shrink
d) . . . all of the above
e) you could never tell your speed by changes in you
2) Astronomers on Earth measure a distant star to be eight light years away, and when they decide to
send an astronaut to explore it at nearly the speed of light, the astronaut has only aged two years,
while several years pass on earth. When they discuss the time difference, the astronaut says that it
is because of time dilation, yet the astronomers say it must be due to length contraction. Who is
right?
a) the astronomers
b) the astronaut
c) neither, the reason lies in relativistic momentum
d) they are both correct, it’s the same phenomenon
Melvin J. Vaughn Page 8 of 61 West Valley College