Light Reflection and Refraction

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Which phenomenon describes light changing direction upon striking a surface?

Absorption
Reflection (correct)
Refraction
Scattering

What is the standard value for the speed of light in a vacuum?

3.00 x 10^9 m/s
3.00 x 10^6 m/s
3.00 x 10^8 m/s (correct)
3.00 x 10^7 m/s

In geometrical optics, what constitutes a ray of light?

A stream of particles (photons) (correct)
A wave of electromagnetic energy
A single point of light
An area of illuminated space

What occurs during specular reflection?

Each incident ray is reflected off in a single direction. (A) Signup and view all the answers

For reflection to occur, what must be true of the incident ray, the reflected ray, and the normal to the surface?

They must all lie in the same plane. (C) Signup and view all the answers

What determines the amount a light ray bends when crossing from one material to another?

The difference in index of refraction between the two materials. (C) Signup and view all the answers

Which scientist is credited with demonstrating the wave nature of light through interference?

Young (D) Signup and view all the answers

Which of the following best describes diffuse reflection?

Light scattering into many directions from a rough surface. (B) Signup and view all the answers

What phenomenon did Einstein explain in 1905 that supported the particle nature of light?

Photoelectric effect (A) Signup and view all the answers

If a light beam enters a medium with a higher index of refraction, how does its behavior change?

It bends towards the normal. (A) Signup and view all the answers

In the context of dispersion through a prism, what does the apex angle (A) primarily influence?

The overall amount of deviation of light rays. (B) Signup and view all the answers

How do primary colors combine to form secondary colors in the context of light?

By mixing them in specific ratios to create new hues. (B) Signup and view all the answers

What is the role of the cornea in the human eye as an optical system?

To primarily focus incoming light. (A) Signup and view all the answers

How does the crystalline lens adjust to focus on objects at varying distances?

By altering its curvature and thickness. (D) Signup and view all the answers

What is the primary function of the iris in the human eye?

To control the amount of light entering the eye. (B) Signup and view all the answers

What is the refractive index of the fluids filling the cavity of the eye?

Approximately the same as water. (C) Signup and view all the answers

What happens to the focusing power of the eye when the ciliary muscle is relaxed?

It is at its minimum. (B) Signup and view all the answers

In the human eye, what process is primarily responsible for adjusting focus to view objects at different distances?

Accommodation (C) Signup and view all the answers

Why is vision considered such a crucial sensory input for humans?

It is estimated to account for about 70% of a person's sensory input. (A) Signup and view all the answers

What would be observed if red and green primary colors of light are mixed together?

Yellow light (A) Signup and view all the answers

According to Snell's law, what happens to the angle of refraction when light passes from a medium with a lower refractive index to a medium with a higher refractive index?

The angle of refraction decreases. (D) Signup and view all the answers

What conditions are necessary for total internal reflection to occur at the interface between two media?

Light must travel from a higher to a lower refractive index medium, and the angle of incidence must be greater than the critical angle. (B) Signup and view all the answers

In the context of fiber optics, what phenomenon enables the transmission of signals over long distances?

Total internal reflection (C) Signup and view all the answers

A lens with a focal length of 25 cm is used to form an image. What is the power of this lens, expressed in diopters?

4.0 D (D) Signup and view all the answers

White light is passed through a prism, resulting in dispersion. Which color of light is refracted the most?

Violet (B) Signup and view all the answers

Two thin lenses with focal lengths $f_1 = 10\text{ cm}$ and $f_2 = 20\text{ cm}$ are placed very close together. What is the effective power of the combined lens system?

15.0 D (D) Signup and view all the answers

In the lens-maker's equation, what does the term 'radius of curvature' refer to?

The radius of the circular arc that forms the lens surface. (C) Signup and view all the answers

How does the refractive index of a medium relate to the speed of light in that medium?

The refractive index is inversely proportional to the speed of light. (D) Signup and view all the answers

What is the role of lenses in optical instruments like cameras and telescopes?

To form images by refraction. (D) Signup and view all the answers

If a light ray strikes an interface at the critical angle, what happens to the refracted ray?

It is refracted at an angle of 90 degrees along the interface. (D) Signup and view all the answers

What is the primary function of the iris within the eye as an optical system?

To act as the entrance aperture, controlling the amount of light entering the eye. (D) Signup and view all the answers

Why does the crystalline lens contribute less to the overall focusing power of the eye compared to the cornea?

The index of refraction of the crystalline lens is only slightly greater than the surrounding fluid. (D) Signup and view all the answers

Which type of photoreceptor cell is primarily responsible for detailed color vision in daylight conditions?

Cones (B) Signup and view all the answers

What is presbyopia, and how does it manifest with age?

A decrease in the accommodation of the eye, causing the near point to shift further away. (C) Signup and view all the answers

How does the eye adjust when viewing distant objects?

The relaxed eye focuses parallel light rays onto the retina. (B) Signup and view all the answers

What is the significance of the fovea in the retina?

It is a depression consisting entirely of cones, providing the most detailed vision. (D) Signup and view all the answers

If a 40-year-old person is experiencing difficulty reading small print, which condition is most likely the cause?

Presbyopia (D) Signup and view all the answers

In conditions with adequate light, why is the image quality best when the iris is at its smallest possible aperture?

A smaller aperture reduces spherical aberrations and increases the depth of field. (B) Signup and view all the answers

What distinguishes rods from cones in the retina regarding their function?

Rods provide vision in dim light, while cones are responsible for sharp color vision in daylight. (C) Signup and view all the answers

When an eye scans a scene, what is the purpose of projecting the region of greatest interest onto the fovea?

To obtain the most detailed vision of that region. (D) Signup and view all the answers

Early Light Theory

Before the 19th century, light was considered a stream of particles.

Young's Interference

Light rays interfere with one another under appropriate conditions. Demonstration of the wavelike nature of light.