Which of the following phenomenon of light forms a rainbow?
1. reflection of light
2. refraction
3. total internal reflection
4. both (2) and (3)
There are certain materials developed in laboratories that have a negative refractive index (figure). A ray incident from the air (medium-\(1\)) into such a medium (medium-\(2\)) shall follow a path given by:
1. | |
2. | |
3. | |
4. |
A graph is plotted between the angle of deviation \(\delta\) in a triangular prism and the angle of incidence as shown in the figure. Refracting angle of the prism is:
1. | \(28^\circ~\) | 2. | \(48^\circ~\) |
3. | \(36^\circ~\) | 4. | \(46^\circ~\) |
An object is at a distance of \(30~\text{cm}\) in front of a concave mirror of focal length \(10~\text{cm}\). The image of the object will be:
1. | smaller in size. |
2. | inverted. |
3. | between focus and centre of curvature. |
4. | all of these. |
Suppose that the lower half of the concave mirror’s reflecting surface in the given figure is covered with an opaque (non-reflective) material. What effect will this have on the image of an object placed in front of the mirror?
1. | the image will show only half of the object |
2. | the image will show the whole of the object |
3. | the intensity of the image will be low |
4. | both (2) and (3) |
A mobile phone lies along the principal axis of a concave mirror, as shown in the figure. Then,
1. | the magnification is not uniform due to the length of the object along the principal axis. |
2. | the distortion of the image depends on the location of the phone with respect to the mirror. |
3. | both (1) and (2) |
4. | none of these |
Given below are two statements:
Assertion (A): | When white light is incident on a prism it will disperse. |
Reason (R): | The refractive index of a medium depends on the wavelength of light. |
1. | Both (A) and (R) are true and (R) is the correct explanation of (A). |
2. | Both (A) and (R) are true but (R) is not the correct explanation of (A). |
3. | (A) is true but (R) is false. |
4. | Both (A) and (R) are false. |
Given below are two statements:
Assertion (A): | A beam of white light passing through a thin hollow prism does not give spectrum. |
Reason (R): | The speed of light inside and outside the prism is same. |
1. | Both (A) and (R) are true and (R) is the correct explanation of (A). |
2. | Both (A) and (R) are true but (R) is not the correct explanation of (A). |
3. | (A) is true but (R) is false. |
4. | Both (A) and (R) are false. |
Assertion (A): | For a simple microscope, the angular size of the object equals the angular size of the image. |
Reason (R): | Magnification is achieved as the small object can be kept much closer to the eye than \(25~\text{cm}\) and hence it subtends a large angle. |
1. | (A) is True but (R) is False. |
2. | Both (A) and (R) are True but (R) is not the correct explanation of (A). |
3. | Both (A) and (R) are True and (R) is the correct explanation of (A). |
4. | (A) is False but (R) is True. |
1. | \(2~\text{cm}\) | 2. | \(20~\text{cm}\) |
3. | \(115~\text{cm}\) | 4. | \(230~\text{cm}\) |