Olympiad Test: Light - 2 - Class 8 MCQ

A distance of 10 cm cannot be the answer, as at this distance even the vision of a person with normal eyes will also get blurred. Therefore, the object placed at a distance of 25 cm from the eye will look blurry to a person suffering from hypermetropia.

Second law of reflection: According to the second law, the angle of reflection is always equal to the angle of incidence. This ray of light will be reflected back along the same path.

- Looking Glass: A plane mirror is used in looking glasses to reflect a clear image of the person or object in front of it.

- Solar Cookers: Plane mirrors are used in solar cookers to reflect and concentrate sunlight onto a specific spot, increasing the temperature for cooking.

- Kaleidoscope: In a kaleidoscope, plane mirrors are placed at angles to create multiple reflections, resulting in beautiful, symmetrical patterns.

- Conclusion: All of these objects utilize plane mirrors for their respective functions. Therefore, the correct answer is D: all of these.

- An opaque object absorbs some of the light that hits it and reflects the rest.
- These objects do not allow light to pass through them, hence they are not transparent.
- The reflection from opaque objects can vary depending on their surface characteristics.
- A shining object reflects more light, often specularly, which might cause a glossy appearance.
- Rough surfaces scatter reflected light in many directions, but they are still opaque.
- Therefore, the correct answer is A: opaque.

- The human brain interprets images formed on the retina.
- The lens of the eye projects an inverted image onto the retina.
- The brain processes this inverted image and flips it to perceive it as erect.
- The perceived size is generally consistent with our experience of the object’s size, thanks to mental processing.
- Therefore, the brain interprets the image as erect and of correct size, making option A the correct answer.