Explanation

Total internal reflection occurs when a light wave reaches the boundary between a denser medium and a rarer medium.

All of the light is reflected back into the denser medium.

Explanation

• A magnifying glass, also known as a convex lens.
• It forms an enlarged virtual image that is upright.

The image formed by a magnifying glass:

• Image type: Virtual
• Orientation: Upright
• Size: Enlarged

Explanation

The human eye acts like a Camera, capturing light and focusing it onto the retina to form an image.

The eye's lens, aperture, and retina work together to create a visual representation of the world, similar to a camera's mechanism.

Explanation

Telescopes are designed to collect and magnify light from distant objects, such as stars, planets, and galaxies.

They are ideal for viewing faint or dim objects in the night sky, as they can gather more light than the human eye alone.

Explanation

The critical angle is the angle of incidence above which total internal reflection occurs.

It can be calculated using Snell's law:

n1 sin(θ1) = n2 sin(θ2)

where n1 = 1.33 (refractive index of water), θ1 = critical angle, n2 = 1 (refractive index of air), and θ2 = 90° (angle of refraction).

Rearranging the equation to solve for θ1, we get:

θ1 = arcsin(n2 / n1)

Substituting the values, we get:

θ1 = arcsin(1 / 1.33) ≈ 48.8°

So, the critical angle is approximately 48.8°.

Explanation

The eyepiece lens has a shorter focal length compared to the objective lens.

It typically around 1-2 cm.

Explanation

• When a light ray enters from a denser medium to a rarer medium, it bends away from the normal (a line perpendicular to the surface).

Key Points:

• Denser to rarer: Away from normal
• Rarer to denser: Toward normal

Explanation

• Dispersion is the optical phenomenon where white light is split into its constituent colors, also known as a spectrum.
• This occurs when light passes through a medium with a refractive index that varies with wavelength, such as a prism.

The process of dispersion involves two stages:

1. Refraction (bending of light)
2. Separation of colors (splitting into distinct colors)

The seven distinct colors that make up the visible spectrum, in order, are:

1. Red
2. Orange
3. Yellow
4. Green
5. Blue
6. Indigo
7. Violet

Explanation

When white light passes through a prism, it is refracted, or bent, and split into its individual colors, a process known as dispersion.

The order of deviation is:

• Violet (most deviated)
• Blue
• Green
• Yellow
• Red (least deviated)

Explanation

• Television remote controllers use infrared (IR) waves to transmit commands to the TV.
• IR waves are a type of electromagnetic radiation with a frequency too low to be seen by the human eye.
• They are widely used in remote control applications, such as:
• TV remote controls
• Air conditioners
• DVD players
• Garage door openers