Light,Human Eye, Electricity & Magnetic Effect of Current

The picture above displays which property of images formed by plane mirrors?

• the image being perpendicular

• the image being virtual

• the image being laterally inverted

• the image being enlarged

Answer explanation

The image formed by a plane mirror is laterally inverted, meaning it appears reversed from left to right. This is a key characteristic of images in plane mirrors, distinguishing them from other types of images.

An image that is virtual is one in which:

• the image is larger than the object

• the image is reversed side to side

• the image is real and can be formed on a screen

• the image is not real and cannot be formed on a screen

Answer explanation

A virtual image is formed by diverging rays and cannot be projected onto a screen, making the correct choice "the image is not real and cannot be formed on a screen." Other options describe characteristics of real images.

Light has the highest velocity in which medium?
flint glass n=1.70
barium glass n=1.60
crown glass n=1.523
water n=1.33
diamond n=2.45

• diamond

• water

• flint glass

• barium glass

Answer explanation

Light travels fastest in a medium with the lowest refractive index. Among the given options, water has the lowest refractive index (n=1.33), allowing light to have the highest velocity in that medium.

Tags

NGSS.HS-PS4-1

According to Willebord Snell, light passing from air to glass will cause the light to

• maintain its original speed 

• accelerate while it is in glass

• increase its speed

• reduce its speed

Answer explanation

According to Willebord Snell's law, when light passes from air (a less dense medium) to glass (a denser medium), it slows down. Therefore, the correct answer is that light will reduce its speed.

Tags

NGSS.HS-PS4-1

A ray of light passes from glass into air. The angle of refraction will be:

• equal to angle of incidence

• greater than angle of incidence

• smaller than angle of incidence

• 45

Answer explanation

When light passes from glass (denser medium) to air (less dense medium), it speeds up, causing the angle of refraction to be greater than the angle of incidence, according to Snell's Law.

Total internal reflection is the complete reflection of a light ray back into its original medium. 

• true 

• false 

Answer explanation

Total internal reflection occurs when a light ray hits the boundary of two media at an angle greater than the critical angle, resulting in the light being completely reflected back into the original medium. Therefore, the statement is true.

The first part of the eye that light hits. 

• lens

• cornea

• pupil

• retina

Answer explanation

The cornea is the first part of the eye that light hits. It acts as a protective layer and helps to focus light before it passes through the pupil and lens.

Following controls and regulates the amount of light entering the eye

• Iris

• Pupil

• Retina

• Corena

Answer explanation

The pupil is the opening in the center of the iris that controls the amount of light entering the eye. It adjusts in size to regulate light exposure, while the iris surrounds and controls the size of the pupil.

How can hypermetropia be corrected?

• By using concave lens

• By using convex lens

• By using bifocal lens

Answer explanation

Hypermetropia, or farsightedness, is corrected using convex lenses. These lenses help focus light directly onto the retina, allowing for clearer vision of nearby objects, unlike concave lenses which are used for myopia.

Tags

NGSS.MS-PS4-2

Q. Where is rods and cones are located in our eyes?

• Retina

• Nervous

• Cornea

• Optic nerve

Answer explanation

Rods and cones are photoreceptor cells located in the retina of the eye. They are responsible for detecting light and color, making the retina the correct answer.