Solving Power Problems: Finding d & l

  • Thread starter Thread starter PixelHarmony
  • Start date Start date
  • Tags Tags
    Power
Click For Summary
SUMMARY

This discussion focuses on solving diffraction-related problems using the equation sin(Xmin) = Xmin = 1.22 (lambda/D). In part (a), the minimum separation between two stars, photographed with a telescope having a 2.32 m aperture and light wavelength of 461 nm, is calculated to be 0.248 mm at a distance of 1022 m. In part (b), the wavelength of light emitted from a car's taillights, observed at a distance of 13.8 km with a pupil diameter of 6.7 mm, is determined using the same diffraction principles.

PREREQUISITES
  • Understanding of diffraction and angular separation
  • Familiarity with the equation sin(Xmin) = Xmin = 1.22 (lambda/D)
  • Knowledge of basic optics, including aperture size and wavelength
  • Ability to perform unit conversions (e.g., nm to m, km to m)
NEXT STEPS
  • Study the principles of diffraction and how they apply to telescopes
  • Learn about the effects of aperture size on resolving power in optical systems
  • Explore the relationship between wavelength and angular separation in optics
  • Investigate the impact of the index of refraction on light behavior in different mediums
USEFUL FOR

Students and professionals in physics, particularly those focusing on optics, astronomy, and engineering, will benefit from this discussion. It is also valuable for anyone interested in understanding the principles of light diffraction and its practical applications.

PixelHarmony
Messages
2
Reaction score
0
Easy Resolving Power Problem

Yet I can't get the answers. Can someone please help me?

sin(Xmin) = Xmin = 1.22 (lambda/D)

(a) Two stars are photographed utilizing a telescope with a circular aperture of diameter of 2.32 m and light with a wavelength of 461 nm. If both stars are 1022 m from us, what is their minimum separation so that we can recognize them as two stars (instead of just one)?

d = ? m*****

(b) A car passes you on the highway and you notice the taillights of the car are 1.14 m apart. Assume that the pupils of your eyes have a diameter of 6.7 mm and index of refraction of 1.36. Given that the car is 13.8 km away when the taillights appear to merge into a single spot of light because of the effects of diffraction, what wavelength of light does the car emit from its taillights (what would the wavelength be in vacuum)?

l = ? nm*****
 
Last edited:
Physics news on Phys.org
nevermind i got them
 


To solve these problems, we need to use the equation sin(Xmin) = Xmin = 1.22 (lambda/D), where Xmin is the minimum angular separation between the two objects, lambda is the wavelength of light, and D is the diameter of the aperture. We can rearrange this equation to solve for D by dividing both sides by 1.22 and multiplying by lambda. This gives us D = lambda / 1.22sin(Xmin).

(a) For the first problem, we are given the diameter of the aperture (D = 2.32 m) and the wavelength of light (lambda = 461 nm = 4.61 x 10^-7 m). We are also given the distance to the stars (r = 1022 m). Plugging these values into the equation, we get:

Xmin = 1.22 (4.61 x 10^-7 m) / (2.32 m) = 2.43 x 10^-7 rad

To find the minimum separation between the stars, we can use the formula s = rXmin, where s is the separation between the stars and r is the distance to the stars. Plugging in the values, we get:

s = (1022 m)(2.43 x 10^-7 rad) = 2.48 x 10^-4 m = 0.248 mm

So the minimum separation between the stars should be 0.248 mm for us to be able to recognize them as two separate objects.

(b) For the second problem, we are given the distance to the car (r = 13.8 km = 1.38 x 10^4 m) and the diameter of our pupils (D = 6.7 mm = 6.7 x 10^-3 m). We are also given the index of refraction of our eyes (n = 1.36). We can use the same equation as before, but this time we need to solve for lambda. Rearranging the equation, we get:

lambda = D1.22sin(Xmin)

To find Xmin, we can use the formula Xmin = s/r, where s is the separation between the taillights and r is the distance to the car. Plugging in the values, we get:

Xmin = (1.14 m)(1.38 x 10^4 m)^-
 

Similar threads

  • · Replies 5 ·
Replies
5
Views
4K
  • · Replies 1 ·
Replies
1
Views
3K
Replies
6
Views
3K
  • · Replies 2 ·
Replies
2
Views
4K
  • · Replies 4 ·
Replies
4
Views
5K
  • · Replies 4 ·
Replies
4
Views
4K
  • · Replies 2 ·
Replies
2
Views
8K
  • · Replies 7 ·
Replies
7
Views
4K
  • · Replies 1 ·
Replies
1
Views
6K
  • · Replies 4 ·
Replies
4
Views
3K