Refraction Of Light At Curved Surfaces (VSAQs)
Physical Science | 4. Refraction Of Light At Curved Surfaces – VSAQs:
Welcome to VSAQs in Chapter 4: Refraction Of Light At Curved Surfaces. This page contains the most important VSAQs in this chapter. Aim to secure top marks in your exams by understanding these clear and straightforward Very Short Answer Questions.
VSAQ-1 : Mention any two uses of convex lenses.
- As Simple Microscopes:
Watch repairers and palmists use convex lenses as simple microscopes to magnify small objects for detailed examination. - For Concentrating Sunlight and Aiding in Reading:
Convex lenses can also be used as burning glasses to concentrate sunlight and create a focused beam of light, as well as reading glasses to aid people with presbyopia in reading and other close-up tasks.
VSAQ-2 : Complete the following ray diagram.
VSAQ-3 : Does the focal length of lens of same in all media ? Guess and write.
- Variation of Focal Length in Different Media: No, the focal length of a lens is not the same in all media.
- Influence of Refractive Index: The focal length of a lens changes when it is placed in different media with varying refractive indices.
- Effect of Light Bending: When light passes through different media, it bends at different angles, affecting the path and focal length of the lens.
- Conclusion on Focal Length Variability: Therefore, the focal length of a lens is not constant and may vary depending on the medium in which it is placed.
VSAQ-4 : Complete the following ray diagram.
VSAQ-5 : What happens to the image, if a convex lens is made up of two different transparent materials, as shown in figure ?
- Effect of Different Materials on Convex Lens:
When a convex lens is made up of two different transparent materials with different refractive indices, it will create two images. - Light Bending at Material Interface:
This is because light rays passing through the lens will bend differently at the interface between the two materials due to the change in refractive index. - Formation of Two Images:
Each interface will produce its own image, resulting in the formation of two images instead of one. - Dependency on Refractive Indices and Curvature:
The position and characteristics of these images will depend on the specific refractive indices and curvature of the lens surfaces.
VSAQ-6 : Write the list of materials required for the experiment to find the focal length of a convex lens.
- Primary Equipment:
- Convex lens (with known focal length)
- Optical bench or meter scale
- Lens holder or lens stand
- Light Source and Projection Screen:
- Candle or light source
- White screen or a piece of paper
- Measurement Tools:
- Ruler or measuring tape
- Protractor (optional)
- Additional Accessories:
- Lens cleaning cloth (for maintenance)
- Stand or clamp (for supporting the light source)
- Purpose of Materials: These materials are essential for setting up and conducting the experiment to determine the focal length of a convex lens through the lens formula or graphical method.