Chapter 28, Problem 34PE

### College Physics

1st Edition
Paul Peter Urone + 1 other
ISBN: 9781938168000

Chapter
Section

### College Physics

1st Edition
Paul Peter Urone + 1 other
ISBN: 9781938168000
Textbook Problem

# (a) All but the closest galaxies are receding from our own Milky Way Galaxy. If a galaxy 12.0 × 10 9   ly ly away is receding from us at 0. 0.900c, at what velocity relative to us must we send an exploratory probe to approach the other galaxy at 0.990c, as measured from that galaxy? (b) How long will it take the probe to reach the other galaxy as measured from the Earth? You may assume that the velocity of the other galaxy remains constant. (c) How long will it then take for a radio signal to be beamed back? (All of this is possible in principle, but not practical.)

To determine

(a)

The velocity to which we have to send the exploratory probe so that it can approach at the other galaxy.

Explanation

Given info:

• The galaxy is receding from us with speed 0.900â€‰c.
• The relative speed of the exploratory probe about galaxy is 0.990â€‰c.
• The galaxy is 12Ã—109â€‰ly away from us.

Formula used:

Formula to find the velocity of space probe sent by us to approach another galaxy is,

â€ƒâ€ƒu'â€‰=â€‰uâˆ’v1âˆ’vuc2

Here, uâ€‰is the velocity of the probe relative to the galaxy, vrelative velocity between Earth and galaxy, u'is the velocity of the probe with respect the Earth and cis the speed of light

To determine

(b)

The time taken by probe to reach at the other galaxy.

To determine

(c)

The time taken by radio signals to beam back.

### Still sussing out bartleby?

Check out a sample textbook solution.

See a sample solution

#### The Solution to Your Study Problems

Bartleby provides explanations to thousands of textbook problems written by our experts, many with advanced degrees!

Get Started