Bending of light in a uniform gravitational field

In summary, according to the homework statement, a light pulse emitted in the positive x direction travels 10 s in a uniform gravitational field of 100 m/s^2. The gravitational field points in the negative y direction. The displacement of the light pulse in the y direction is 10 s.
  • #1
vuser88
14
0

Homework Statement


This is supposed to be a simple problem that shows that light bends or gets pulled in a gravitational field.


A light pulse emitted in the positive x direction travels 10 s in a uniform gravitational field of 100 m/s^2. the gravitational field points in the negative y direction. find the displacement of the light pulse in the y direction.

help, i don't even know the equations relating the two. any help would be greatly appriciated.

i don't even know how to relate the two. we were given only one equation.


Homework Equations



uy = c (1 – v2/c2)1/2


The Attempt at a Solution



dont even know where to start. i understand that light will be curved down. it travels at the speed c for 10 seconds so that gives me a distance... but that as far as i can get

this is an intro class to cosmology

thank you for any help.
 
Physics news on Phys.org
  • #2
Btw can anyone suggest some good intro books to comsology that has lots of examples. the one we are using is by ryder. there are no examples
 
  • #3
you can use E=mc^2 hf=mc^2 , to get an effective mass for the photon and then use Newtons law for gravitation to get an estimate of the force between them. But i think its off by a factor of 2 from GR.
 
  • #4
But how would the force help me... I am thinking that this can be treated like a free throw problem... but I am not sure...thnk u
 
  • #5
Cragar is right. Using Newton would understate the effect by about 2:1.

This requires the General Theory of Relativity.
 
Last edited:
  • #6
You could resort to using an argument based on the equivalence principle, but I think you'd be begging the question. You're probably expected to do the calculation using GR.

Do you have the spacetime metric that corresponds to a uniform gravitational field?
 
  • #7
We didnt talk about metrics bc the class is supposed to not cover and mathematics of GR. Should i assume a metric.
How would i go about solving it then if i shouldn't use Newtons method...
 

What is the bending of light in a uniform gravitational field?

The bending of light in a uniform gravitational field, also known as gravitational lensing, is the phenomenon where light is deflected as it passes through a gravitational field, such as that of a massive object like a star or galaxy.

How does the bending of light in a uniform gravitational field occur?

The bending of light in a uniform gravitational field occurs because of the curvature of space-time caused by the presence of a massive object. This curvature affects the path of light, causing it to bend towards the object.

What is the significance of the bending of light in a uniform gravitational field?

The bending of light in a uniform gravitational field has significant implications in astronomy and cosmology. It allows us to study and measure the mass and distribution of matter in the universe, including dark matter, which cannot be directly observed.

Can we observe the bending of light in a uniform gravitational field?

Yes, the bending of light in a uniform gravitational field can be observed through various methods, such as gravitational lensing, where the light from distant objects is bent and magnified by the gravitational pull of a massive object in the foreground.

Are there any real-life applications of the bending of light in a uniform gravitational field?

Yes, the bending of light in a uniform gravitational field has practical applications, such as in the development of telescopes and imaging techniques that use gravitational lensing to capture images of distant and faint objects in space.

Similar threads

  • Special and General Relativity
Replies
11
Views
172
  • Special and General Relativity
Replies
22
Views
2K
  • Special and General Relativity
Replies
15
Views
2K
  • Introductory Physics Homework Help
Replies
4
Views
689
Replies
8
Views
3K
Replies
40
Views
2K
  • Special and General Relativity
Replies
14
Views
1K
  • Introductory Physics Homework Help
Replies
5
Views
1K
  • Special and General Relativity
Replies
21
Views
4K
  • Advanced Physics Homework Help
Replies
14
Views
2K
Back
Top