RAY OPTICS AND OPTICAL INSTRUMENTS-20 Quiz

JEE Advanced Physics Syllabus can be referred by the IIT aspirants to get a detailed list of all topics that are important in cracking the entrance examination. JEE Advanced syllabus for Physics has been designed in such a way that it offers very practical and application-based learning to further make it easier for students to understand every concept or topic by correlating it with day-to-day experiences. In comparison to the other two subjects, the syllabus of JEE Advanced for physics is developed in such a way so as to test the deep understanding and application of concepts.

Q1. Statement 1: The cloud in sky generally appear to be whitish
Statement 2: Diffraction due to cloud is efficient in equal measure at all wavelengths
•   Statement 1 is True, Statement 2 is True; Statement 2 is correct explanation for Statement 1
•   Statement 1 is True, Statement 2 is True; Statement 2 is not correct explanation for Statement 1
•   Statement 1 is True, Statement 2 is False
•   Statement 1 is False, Statement 2 is True
Solution
The clouds consist of dust particles and water droplets. Their size is very large as compared to the wavelength of the incident light from the sun. So there is very little scattering of light. Hence the light which we receive through the clouds has all the colours of light. As a result of this, we receive almost white light. Therefore, the cloud are generally white

Q2.Statement 1: Glass is transparent but its powder seems opaque. When water is poured over it, it becomes transparent.
Statement 2: Light gets refracted through water.
•   Statement 1 is True, Statement 2 is True; Statement 2 is correct explanation for Statement 1
•   Statement 1 is True, Statement 2 is True; Statement 2 is not correct explanation for Statement 1
•   Statement 1 is True, Statement 2 is False
•   Statement 1 is False, Statement 2 is True
Solution
In case of powdered glass, irregular reflection takes place from various particles. Thus, light is sent back into the same medium. Therefore, it looks opaque. On putting water over the powder incident light gets refracted through water. That is why it looks transparent.Read more on Sarthaks.com - https://www.sarthaks.com/279915/glass-transparent-nature-glass-powder-opaque-water-poured-over-again-becomes-transparent.

Q3.  Statement 1: A convex lens of focal length f(Î¼=1.5) behaves as a diverging lens when immersed in carbon di-sulphide of higher refractive index (Î¼=1.65)
Statement 2: The focal length of a lens does not depend on the color of light used
•   Statement 1 is True, Statement 2 is True; Statement 2 is correct explanation for Statement 1
•   Statement 1 is True, Statement 2 is True; Statement 2 is not correct explanation for Statement 1
•   Statement 1 is True, Statement 2 is False
•   Statement 1 is False, Statement 2 is True
Solution
Since Î¼=Î¼_g/Î¼_cs =1.5/1.65 ∠1
From 1/f=(Î¼-1)(1/R_1 -1/R_2 )⇒f less than 0
Therefore, the lens behaves as a diverging lens
Hence, (b) is correct option

Q4. Statement 1: An empty test tube dipped into water in a beaker appears silver, when viewed from a suitable direction
Statement 2: Due to refraction of light, the substance in water appears silvery
•   Statement 1 is True, Statement 2 is True; Statement 2 is correct explanation for Statement 1
•   Statement 1 is True, Statement 2 is True; Statement 2 is not correct explanation for Statement 1
•   Statement 1 is True, Statement 2 is False
•   Statement 1 is False, Statement 2 is True
Solution
The ray of light incident on the water air interface suffers total internal reflections, in that case the angle of incidence is greater than the critical angle. Therefore, if the tube is viewed from suitable direction (so that the angle of incidence is greater than the critical angle), the rays of light incident on the tube undergoes total internal reflection. As a result, the test tube appears as highly polished i.e. silvery

Q5. Statement 1: The resolving power of an electron microscope is higher than that of an optical microscope
Statement 2: The wavelength of electron is more than the wavelength of visible light
•   Statement 1 is True, Statement 2 is True; Statement 2 is correct explanation for Statement 1
•   Statement 1 is True, Statement 2 is True; Statement 2 is not correct explanation for Statement 1
•   Statement 1 is True, Statement 2 is False
•   Statement 1 is False, Statement 2 is True
Solution
The wavelength of wave associated with electron (de Broglie waves) is less than that of visible light. We know that resolving power is inversely proportional to wavelength of wave used in microscope. Therefore the resolving power of an electron microscope is higher than that of an optical microscope

Q6. Statement 1: Blue colour of sky appears due to scattering of blue colour
Statement 2: Blue colour has shortest wave length in visible spectrum
•   Statement 1 is True, Statement 2 is True; Statement 2 is correct explanation for Statement 1
•   Statement 1 is True, Statement 2 is True; Statement 2 is not correct explanation for Statement 1
•   Statement 1 is True, Statement 2 is False
•   Statement 1 is False, Statement 2 is True
Solution
I (scattering of light) ∝1/Î»^4 , blue light has small wavelength and order of wavelength of blue light is nearly equal to size of scattered particle of sky and blue scattered most not violet even violet has smallest wavelength in visible spectrum.

Q7.Statement 1: Critical angle of light passing from glass to air is minimum for violet colour
Statement 2: The wavelength of violet light is greater than the light of other colours
•   Statement 1 is True, Statement 2 is True; Statement 2 is correct explanation for Statement 1
•   Statement 1 is True, Statement 2 is True; Statement 2 is not correct explanation for Statement 1
•   Statement 1 is True, Statement 2 is False
•   Statement 1 is False, Statement 2 is True
Solution
Î¼∝1/Î»∝1/C.Î»_V is least so C_V is also least. Also the greatest wavelength is for red colour

Q8. Statement 1: The mirrors used in search lights are parabolic and not concave spherical.
Statement 2: In a concave spherical mirror the image formed is always virtual.
•   Statement 1 is True, Statement 2 is True; Statement 2 is correct explanation for Statement 1
•   Statement 1 is True, Statement 2 is True; Statement 2 is not correct explanation for Statement 1
•   Statement 1 is True, Statement 2 is False
•   Statement 1 is False, Statement 2 is True
Solution
A search light produces an intense parallel beam of light. This requires a reflector of large aperture. When a sources are placed at the focus of a large concave mirror, only the paraxial rays (not the marginal rays) are reflected as parallel beam. But when a source is placed at the focus of parabolic mirror all the rays are reflected as an intense parallel beam. Reason is wrong as concave mirror can produce both real and virtual image.

Q9. Statement 1: Keeping a point object fixed, if a plane mirror is moved, the image will also move
Statement 2: In case of a plane mirror, distance of object and its image is equal from any point on the mirror
•   Statement 1 is True, Statement 2 is True; Statement 2 is correct explanation for Statement 1
•   Statement 1 is True, Statement 2 is True; Statement 2 is not correct explanation for Statement 1
•   Statement 1 is True, Statement 2 is False
•   Statement 1 is False, Statement 2 is True
Solution
If the mirror is shifted parallel to itself such that the velocity of the mirror is parallel to its surface, the image shall not shift. Hence, Statement I is false

Q10. Statement 1: The refractive index of a prism depends only on the kind of glass of which it is made of and the colour of light
Statement 2: The refractive index of a prism depends upon the refracting angle of the prism and the angle of minimum deviation

•   Statement 1 is True, Statement 2 is True; Statement 2 is correct explanation for Statement 1
•   Statement 1 is True, Statement 2 is True; Statement 2 is not correct explanation for Statement 1
•   Statement 1 is True, Statement 2 is False
•   Statement 1 is False, Statement 2 is True
Solution
So refractive index depends on
Refracting angle of the prism
Angle of minimum deviation
And also material of the prism as well as the wavelength of the light i.e., color of the light.

Written by: AUTHORNAME

AUTHORDESCRIPTION

Want to know more

Please fill in the details below:

Latest NEET Articles\$type=three\$c=3\$author=hide\$comment=hide\$rm=hide\$date=hide\$snippet=hide

Name

ltr
item
BEST NEET COACHING CENTER | BEST IIT JEE COACHING INSTITUTE | BEST NEET & IIT JEE COACHING: Ray Optics and Optical Instruments-Quiz-20
Ray Optics and Optical Instruments-Quiz-20