Tag: light, shadows and images

Questions Related to light, shadows and images

For a total internal reflection, which of the following is correct?

  1. Light travel from rarer to denser medium.

  2. Light travel from denser to rarer medium.

  3. Light travels in air only.

  4. Light travels in water only.


Correct Option: B
Explanation:

The total internal reflection occurs when the ray of light is reflected totally into the same medium even without the presence of a mirror. The total internal reflection occurs when a ray of light travels from denser medium to rarer medium.

If the angle of incidence is $70^o$, then calculate the angle between the incidence ray and the reflected ray.

  1. $40^o$

  2. $140^o$

  3. $130^o$

  4. $110^o$


Correct Option: B
Explanation:

Given $\angle i=70^o$
The angle between incident ray and the reflected ray $=2\angle i=140^o$

Which objects use the reflection of light?

  1. Sun glasses

  2. Periscope

  3. Mirror

  4. Side mirror of a car


Correct Option: B,C,D
Explanation:

Periscope, mirror, side mirror of a car use the reflection of light phenomenon.

An ideal mirror :

  1. Absorbs all the amount of light incident on it

  2. Refracts all the light

  3. Reflects all the light

  4. None of the above


Correct Option: C
Explanation:

An ideal mirror is defined as object having a reflecting surface so smooth that it reflect back all the light rays striking without any absorbance and emiittance.

Which of the following statement is/ are correct?
I. A person suffering from myopia can see distant obhects clearly.
II.. The bluish color of water in deep sea is only due to reflection of sky in water.
III. In vacuum, all the colored of the light move with the same speed.
IV. At noon, the sun appears white as light is least scattered

  1. I only

  2. II only

  3. I and II only

  4. III and IV only


Correct Option: C
Explanation:

Myopia is the inability to see objects clearly when they're too far away. People with myopia can often read or see items within a few feet of their face, but distant objects appear blurred. This condition usually develops in an eyeball that's too long from front to back.

The ocean looks blue because red, orange and yellow (long wavelength light) are absorbed more strongly by water than is blue (short wavelength light). So when white light from the sun enters the ocean, it is mostly the blue that gets returned.

The laws of reflection are true for

  1. the plane mirror only

  2. the concave mirror  and convex mirror

  3. the convex mirror only

  4. all reflecting surfaces


Correct Option: D
Explanation:

It is a fact that laws of reflection are applicable to all reflecting surfaces.

Shaving mirrors are

  1. convex mirrors

  2. concave mirrors

  3. plane mirrors

  4. none of the above


Correct Option: B
Explanation:

Shaving mirrors are concave mirror, so that when you keep your face near to the focus of the mirror, you get a magnified image.

If a ray of light incident on a plane mirror is such that it makes an angle of $30^{\circ}$ with the mirror, then the angle of reflection is

  1. $30^{\circ}$

  2. $45^{\circ}$

  3. $55^{\circ}$

  4. $60^{\circ}$


Correct Option: D
Explanation:

if angle with the mirror = $30^o$ then angle with the normal = $90^o - 30^o$ = 60$^o$

hence ans. is D

The angle between the original path of the incident ray and the emergent ray coming out of a prism is called angle of

  1. incidence

  2. reflection

  3. prism

  4. deviation


Correct Option: D
Explanation:

Angle of deviation is defined as the angle between incident ray and emergent ray or reflected ray.

The phenomenon that leads to the bouncing back of light rays is called-

  1. Diffraction

  2. Reflection

  3. Dispersion

  4. Refraction


Correct Option: B
Explanation:
$ \bf{Diffraction} $ is the phenomenon of bending of light waves around the corners of an obstacle or aperture, placed in the path of light beam. 

$ \bf{Reflection} $ is the phenomenon in which light rays on striking a polished surface(such as a mirror) bounce back or are sent back into the same medium. 

$\bf{Dispersion} $ is the phenomenon of splitting of white light into its component colours (VIBGYOR) on passing through a glass prism.

$ \bf{Refraction} $ of light is the phenomenon of bending of light or change in the direction of light, when it passes obliquely from one transparent medium to another.

Hence, the correct answer is OPTION B.