Light - Reflection and Refraction Class 10 Worksheet Science

Multiple Choice Questions

Q1: Which phenomenon is responsible for allowing us to see our reflection in a shiny surface? 
(a) Refraction
(b) Absorption
(c) Reflection
(d) Diffraction

Q2: Which type of mirror has a reflecting surface curved inwards? 
(a) Convex Mirror
(b) Concave Mirror
(c) Plane Mirror
(d) Spherical Mirror

Q3: In a plane mirror, the image is: 
(a) Real and inverted
(b) Virtual and erect
(c) Virtual and inverted
(d) Real and erect

Q4: What is the speed of light in a vacuum? 
(a) 3 x 10⁷ m/s
(b) 3 x 10⁸ m/s
(c) 3 x 10⁶ m/s
(d) 3 x 10⁹ m/s

Q5: What is the relationship between focal length and radius of curvature for spherical mirrors? 
(a) f = R
(b) f = R/2
(c) f = 2R
(d) f = 2/R

Fill in the Blanks

Q1: The word "AMBULANCE" is written in reverse direction so that it can be read correctly in the rear-view mirror of vehicles going in front of it. This is an application of ________________. 

Q2: The point on the principal axis where all parallel light rays actually meet or appear to meet after reflection is called the ____________. 

Q3: The bending of a ray of light as it passes from one medium to another is called ______________. 

Q4: The line joining the pole and center of curvature of a spherical mirror is called the ____________.

Q5: The point for a given lens through which any ray passes undeviated is known as the ____________. 

True/False

Q1: The image formed by a concave mirror is always virtual.

Q2: The magnification of a convex lens is always positive.

Q3: In refraction, when light passes from a denser to a rarer medium, the ray bends towards the normal.

Q4: The focal length of a concave lens is positive.

Q5: The magnification of a plane mirror is always +1.

Very Short Answer Questions

Q2: Why do we prefer a convex mirror as a rear-view mirror in vehicles?

Q3: A concave mirror produces three times magnified (enlarged) real image of an object placed at 10 cm in front of it. Where is the image located?

Q4: Light enters from air to glass having refractive index 1.50. What is the speed of light in the glass? The speed of light in vacuum is 3 × 108 m/s.

Q5: You are given kerosene, turpentine and water. In which of these does the light travel fastest? Use the information given in table above.

Q6: Define 1 dioptre of power of a lens.
Q7: Find the power of a concave lens of focal length 2 m.

Q8: Is it possible that a convergent lens in one medium becomes divergent, when placed in another medium?

Q9: Out of convex mirror and a concave mirror, whose focus is situated behind the mirror?

Q10: What is the unit of refractive index?

Q11: An object is placed at a distance of 10 cm from a convex mirror of focal length 15 cm. Find the position and nature of the image.

Q12: An object 5.0 cm in length is placed at a distance of 20 cm in front of a convex mirror of radius of curvature 30 cm. Find the position of the image, its nature and size.

Q13: Find the focal length of a lens of power –2.0 D. What type of lens is this?

Q14: An object of size 7.0 cm is placed at 27 cm in front of a concave mirror of focal length 18 cm. At what distance from the mirror should a screen be placed, so that a sharp focused image can be obtained? Find the size and the nature of the image.

Q15: If a magnification of -1 is to be obtained using a concave mirror of focal length 6 cm, then what should be the position of the object?
Q16:  A 5 cm tall object is placed perpendicular to the principal axis of a convex lens of focal- length 20 cm. The distance of the object from the lens is 30 cm. Find the:
(i) position
(ii) nature
(iii)  size of the image formed. 

Q.17: 4.5 cm needle is placed 12 cm away from a convex mirror of focal length 15 cm. Give the location of image and magnification. Describe what happens to the image as the needle is moved farther from the mirror. 

Q.18: Rohit placed a pencil perpendicular to principal axis in front of a converging mirror of focal length 30 cm. The image formed is twice the size of the pencil. Calculate the distance of the object from the mirror. 

Q.19: One half of a convex lens is covered with a black paper.
(a)Show the formation of image of an object placed at 2F1, of such covered lens with the help of ray diagram. Mention the position and nature of image.
(b)Draw the ray diagram for same object at same position in front of the same lens, but now uncovered. Will there be any difference in the image obtained in the two cases? Give reason for your answer. 

Q.20: 
(a) The refractive index of Ruby is 1.71. What is meant by this statement?
(b) The refractive index of some medium are given below:
Crown glass- 1.52
Water- 1.33
Sapphire- 1.77
In which of the medium is the speed of light
(i)maximum
(ii)minimum
(iii) Calculate speed of light in sapphire. 

You can access the solutions to this worksheet here.