Light – Reflection and Refraction Class 10 MCQ Quiz – Test Your Understanding!

A. Noor, a young student, was trying to demonstrate some properties of light in her science project work. She kept ‘X’ inside the box (as shown in the figure) and with the help of a laser pointer made light rays pass through the holes on one side of the box. She had a small butter paper screen to see the spots of light being cast as they emerged.

Her friend noted the following observations from this demonstration:

1.  Glass is optically rarer than air.
2.  Air and glass allow light to pass through them with the same velocity.
3.  Air is optically rarer than glass.
4. The speed of light through a denser medium is faster than that of a rarer medium.
5.  The ratio of the sin of the angle of incidence in the first medium to the ratio of the sin of the angle of refraction in the second medium gives the refractive index of the second material with respect to the first one.

Which one of the following combinations of the above statements given below is correct?

Sumati wanted to see the stars of the night sky. She knows that she needs a telescope to see those distant stars. She finds out that the telescopes, which are made of lenses, are called telescopes and the ones which are made of mirrors are called reflecting telescopes.

So she decided to make a refracting telescope. She bought two lenses L₁ and L₂ out of which L₁ was bigger and L₂ was smaller. The larger lens gathers and bends the light, while the smaller lens magnifies the image. Big, thick lenses are more powerful. So to see far away, she needed a big powerful lens. Unfortunately, she realized that a big lens is very heavy.

Heavy lenses are hard to make and difficult to hold in the right place. Also since the light is passing through the lens, the surface of the lens has to be extremely smooth. Any flaws in the lens will change the image. It would be like looking through a dirty window.

If the powers of the lenses L₁ and L₂ are in the ratio of 4:1, what would be the ratio of the focal length of L₁ and L₂?

The figure below shows a ray of light as it travels from medium A to medium B. Refractive index of medium B relative to medium A is

A small electric lamp is placed at the focus of a convex lens. When the lamp is switched on, the lens will produce:

In the diagram shown below, a light ray is incident on a convex mirror.

Through which point will the ray travel after reflecting off the mirror?

As a ray of light entered medium P from medium Q, its velocity increased.

What can be said about the refractive index of medium P as compared to that of medium Q?

Sumati wanted to see the stars of the night sky. She knows that she needs a telescope to see those distant stars. She finds out that the telescopes, which are made of lenses, are called telescopes and the ones which are made of mirrors are called reflecting telescopes.

So she decided to make a refracting telescope. She bought two lenses L₁ and L₂ out of which L₁ was bigger and L₂ was smaller. The larger lens gathers and bends the light, while the smaller lens magnifies the image. Big, thick lenses are more powerful. So to see far away, she needed a big powerful lens. Unfortunately, she realized that a big lens is very heavy.

Heavy lenses are hard to make and difficult to hold in the right place. Also since the light is passing through the lens, the surface of the lens has to be extremely smooth. Any flaws in the lens will change the image. It would be like looking through a dirty window.

Sumati bought not-so-thick lenses for the telescope and polished them. What advantages, if any, would she have with her choice of lenses?

A. Noor, a young student, was trying to demonstrate some properties of light in her science project work. She kept ‘X’ inside the box (as shown in the figure) and with the help of a laser pointer made light rays pass through the holes on one side of the box. She had a small butter paper screen to see the spots of light being cast as they emerged.

What could be the ‘X’ that she placed inside the box to make the rays behave as shown?

Examine the below figure and state which of the following options is correct.

(one small box in the figure is equal to 1 cm)

Assertion (A): Refractive index has no units.

Reason (R):  The refractive index is the ratio of two similar quantities.

What is the formula for magnification obtained with a lens?

Consider these indices of refraction:

• Glass: 1.52
• Air: 1.0003
• Water: 1.333

Based on the refractive indices of three materials, arrange the speed of light through them in decreasing order.

In the below diagram light is traveling through different media. It is noted by a scientist that ∠1 = ∠3 = ∠4 but ∠2 = ∠1. Which of the following statement would be correct?

If the real image of a candle flame formed by a lens is three times the size of the flame and the distance between the lens and image is 80 cm, at what distance should the candle be placed from the lens?

No matter how far you stand from this spherical mirror, your image always appears erect. The mirror may be: