Binoculars for Observing Lobsters Underwater - Optics Calculation

  • Thread starter usn7564
  • Start date
  • Tags
    Water
In summary, the problem involves finding the distance between the lenses of a Galilean binoculars used for observing lobsters underwater. The ocular has a focal length of 40mm and the objective is a plano-convex lens with a focal length of 200mm. The tube is filled with air and the refractive indices of water and glass are 1.33 and 1.52, respectively. The lensmaker formula, 1/f = 1/s + 1/s', can be used to solve for the distance between the lenses, but the focal length is affected by the number of surfaces. Any assistance would be appreciated.
  • #1
usn7564
63
0

Homework Statement


A type of binoculars used for observing lobsters 10m below the water surface has an ocular with f = 40mm and an objective with f = 200mm (on the side of the air). The objective is a plano-convex lens. The tube is filled with air. What's the distance between the lenses?

Homework Equations


n_water = 1.33
n_glass = 1.52

1/f = 1/s + 1/s'

[tex]\frac{n_a}{s} + \frac{b}{s'} = \frac{n_b - n_a}{r}[/tex]

The Attempt at a Solution


Tried playing around with the lensmaker formula but not getting past the radius which I presume I can get from f = 200mm, but not quite sure how the focal length is affected by the fact that there are several surfaces.
 
Last edited:
Physics news on Phys.org
  • #2
Any help would be greatly appreciated. EDIT: I forgot to mention that the binoculars are Galilean, not Keplerian.
 

1. How do binoculars enhance the observation of lobsters underwater?

Binoculars are designed to magnify the image of an object, making it appear larger and clearer. When observing lobsters underwater, binoculars allow you to see the details of the lobster's appearance and behavior that may not be visible to the naked eye. This can be especially useful for scientific research and studying the behavior of lobsters in their natural habitat.

2. What is the optimal magnification for binoculars when observing lobsters underwater?

The optimal magnification for binoculars when observing lobsters underwater depends on various factors such as the depth of the water, clarity of the water, and the size of the lobsters. Generally, a magnification of 7x to 10x is recommended for underwater observation as it provides a good balance between magnification and stability.

3. How do I calculate the optics of binoculars for observing lobsters underwater?

The optics of binoculars for observing lobsters underwater can be calculated by taking into account the magnification, objective lens diameter, and exit pupil. The magnification is the number before the "x" symbol, for example, 7x or 10x. The objective lens diameter is the size of the front lens in millimeters, and the exit pupil is the size of the light beam that enters your eye. The larger the exit pupil, the brighter the image will appear.

4. What are some important features to consider when choosing binoculars for observing lobsters underwater?

When choosing binoculars for observing lobsters underwater, some important features to consider include waterproof and fog-proof capabilities, image stabilization, and a wide field of view. Waterproof and fog-proof binoculars are essential for underwater use to prevent damage from moisture and maintain clear vision. Image stabilization helps to reduce shakiness and provide a steady image. A wide field of view allows you to see a larger area and capture more detail.

5. Can binoculars be used for scientific research on lobsters?

Yes, binoculars can be a valuable tool for scientific research on lobsters. They allow for close observation of lobsters in their natural habitat without disturbing their behavior. Binoculars can also be used for measuring the size and movements of lobsters, making them useful for studies on population dynamics and behavior. However, it is important to choose binoculars specifically designed for underwater use and to follow proper research ethics and guidelines when conducting studies on lobsters.

Similar threads

  • Introductory Physics Homework Help
Replies
3
Views
781
  • Introductory Physics Homework Help
Replies
6
Views
1K
  • Introductory Physics Homework Help
Replies
1
Views
1K
  • Introductory Physics Homework Help
Replies
13
Views
2K
  • Introductory Physics Homework Help
Replies
1
Views
2K
  • Introductory Physics Homework Help
Replies
1
Views
2K
  • Introductory Physics Homework Help
Replies
1
Views
1K
  • Introductory Physics Homework Help
Replies
1
Views
1K
  • Introductory Physics Homework Help
Replies
4
Views
2K
  • Introductory Physics Homework Help
Replies
3
Views
2K
Back
Top