Log In Start studying!

Select your language

Suggested languages for you:
Answers without the blur. Sign up and see all textbooks for free! Illustration


Fundamentals Of Physics
Found in: Page 1364

Answers without the blur.

Just sign up for free and you're in.


Short Answer

In the laboratory, one of the l;ines of sodium is emitted at a wavelength of 590.0 nm. In the light from a particular galaxy, however, this line is seen at a wavelength of 602.0 nm. Calculate the distance to the galaxy, assuming that Hubble’s law holds and that the Doppler shift of Eq 37-36 applies.

Thus, the distance of the galaxy is.90.1 Mpc

See the step by step solution

Step by Step Solution

Step 1: Use relativistic Doppler shift formula.

The relativistic Doppler shift formula is:


Step 2: Evaluate the distance of galaxy.

Light of wavelength 590.0 nm is observed to be 602.0 nm. Therefore, the speed of the source can be obtained from the equation.


Solve further,



The Hubble’s law is:


1 Mpc=3.26×106 light-years=3.084×1019km1 Mpc=3.26×106 light-years=3.084×1019km

Therefore, the distance of the galaxy as calculated using the Hubble’s law will be:

d=vH=2.013×102×3×105kms-167kms-1Mpc=90.1 Mpc

Hence, the distance of the galaxy is.90.1 Mpc

Most popular questions for Physics Textbooks


Want to see more solutions like these?

Sign up for free to discover our expert answers
Get Started - It’s free

Recommended explanations on Physics Textbooks

94% of StudySmarter users get better grades.

Sign up for free
94% of StudySmarter users get better grades.