CBSE Worksheet for chapter-8 Light class 10

CBSE Worksheet for chapter-8 Light class 10

Worksheet For class 10

This page is prepared by the Academic team of Physics Wallah which consists of CBSE Board Worksheet for Class 10 Physics . Students of Class 10 Physics can get a free Worksheet for Class 10 Physics in PDF format prepared as per the newest syllabus and examination pattern in your schools.

Standard 10 students can practice questions and answers which are given here for Physics in Grade 10 that will help them to improve their knowledge of all important chapters and their topics. Students can also download free pdf of Class 10 Physics Notes prepared by teachers and solve important problems provided here with solutions on daily basis to get more scores in school exams and tests.

If any students need to take the online test to check their concepts or undertstanding then they can visit Physics Quiz for Class 10 .

Summary

• Refraction of light – Definition, Cause and Effects,
• Laws of Refraction, Refractive index and factors affecting it
• Spherical Lenses – Convex lens and Concave lens
• Rules for formation of images by concave lens and convex lens
• Power of a lens, Lens Formula, Linear Magnification

Section 1 - Objective

Q1. Refractive index of glass with respect to air is 1.5 and refractive index of water with respect to air is 4/3. What will be the refractive index of glass with respect to water?

1. 1
2. 1.5
3. 1.125
4. -10

Q2. A ray of light is incident normally on a rectangular piece of glass. The value of angle of refraction will be :

1. 180°
2. 90°
3. 45°
4. 0°

Q3. The speed of light in vacuum is 3.0 х 10 ⁸ m/s. If the refractive index of a transparent liquid is 4/3, then the speed of light in liquid is :

1. 2.25 х 10 ⁸ m/s
2. 3 х 10 ⁸ m/s
3. 4 х 10 ⁸ m/s
4. 4.33 х 10 ⁸ m/s

Q4. To get a real and inverted image of the same size as that of the object, the object should be placed in front of the convex lens at :

1. F
2. 2F
3. Between F and 2F
4. Away from 2F, where F is focus

Q5. The focal length of a lens of power -2.0 D is :

1. –2.0 m
2. 0.2 m
3. -0.5 m
4. 0.5 m

Q6. Two lenses of power +5D and -5D are placed in close contact. The focal length of the combination is :

1. Zero
2. ∞
3. Zero or ∞
4. None of these

Q7. A student needs a lens of power -2.0 dioptre to correct his distant vision. The focal length of the given lens is :

1. +50 cm
2. -50 cm
3. 100 cm
4. -100 cm

Q8. Focal le​​ngth of coloured goggles (without number) is :

1. Zero
2. Infinity
3. Between zero and infinity
4. None of these

Q9. A glass rod of refractive index 1.42 is immersed in kerosene. The refractive index of kerosene is 1.42. Then the rod will :

1. Appear bent
2. Appear raised above the liquid
3. Become invisible
4. None of these

Q10. The power of lens whose focal length is 25 cm is :

1. 4 dioptre
2. 25 dioptre
3. 0.04 dioptre
4. 2.5 dioptre

Q11. A convex lens forms a real image of a point object placed on its principal axis. If the upper half of the lens is painted black :

1. The image will be shifted backward
2. The image will not be shifted
3. The intensity of the image will decrease
4. Both (B) and (C)

Section 2 - Subjective

Q1. Write any three cases where the image formed by a convex lens is real and inverted?

Q2. Two lenses of power +3.5 D and -2.5 D are placed in contact. Find the power and focal length of the lens combination.

Q3. Calculate the speed and wavelength of light:

1. In glass and
2. In air, when light waves of frequency 6 х 10 ¹⁴ Hz travel from air to glass of μ=1.5.

Q4. Light of wavelength 500 nm in air enters a glass plate of refractive index 1.5. Find:

1. Speed of light in glass
2. Frequency of light in glass
3. Wavelength of light in glass

Q5. State the cause and effect of refraction.

Q6. Explain refraction through a glass slab:

Q7. What is the angle of deviation for a light ray passing through a rack of glass will different reflective which and finally emerging out into the initiate medium?

Q8. Is a bi-convex lens always converging?

Q9. If the reflective index of material is 1.33 what is the velocity of light in this medium?

Q10. What is the wavelength of list cotta frequency 3 X 10 ¹² Hz in a medium of refractive index m= 1.44?

Solutions for Section 1 & 2

Objective Problems:

Subjective Problems:

2. Power=1D, Focal length = 1m.

3. A) V _g =2+ 10 ⁸ ms ^-1 , Wavelength of light in glass = 3.3 x 10 ^-7 m

B) V _a = 3 x 10 ⁸ m/s, Wavelength of light in air = 5 x 10 ^-7 m

4.

A) 2 X10 ⁸ ms ^-1

B) 6 х 10 ¹⁴ Hz

C) 10 ^-6 /3 m