CBSE Class 10 Physics Refraction of Light Worksheet Set A

Question. A beam of light is incident through the holes on side A and emerges out of the hole on the other face of the box as shown in the figure. Which of the following could be inside the box? 
(a) Concave lens
(b) Rectangular glass slab
(c) Prism
(d) Convex lens

Answer : D

Question. If the magnification produced by a lens has a negative value, the image will be
(a) virtual and inverted
(b) virtual and erect
(c) real and erect
(d) real and inverted

Answer : B

Question. The image shows the path of light travelling through a glass slab.
What causes the ray of light to deviate from its original path?
(a) change in the amount of light
(b) change in the direction of wind flow
(c) change in the temperature of the air
(d) change in the density of the medium
Answer : D

Question. As light travels from a rarer to a denser medium it will have
(a) Increased velocity
(b) Decreased velocity
(c) Decreased wavelength
(d) both (b) and (c)
Answer : B

Question. A full length image of a distant tall building can definitely be seen by using
(a) a concave mirror
(b) a convex mirror
(c) a plane mirror
(d) both concave as well as plane mirror
Answer : B

Question. Rakhi conducts an experiment to produce an image of an object on a screen which is placed at 20 cm from the lens. She uses a convex lens of focal length 15 cm for the experiment. Where should she place the object in order to produce the sharpest image?
(a) 8 cm in front of the lens
(b) 15 cm in front of the lens
(c) 20 cm in front of the lens
(d) 60 cm in front of the lens
Answer : D

Question. When light travels from one medium to another which of the following factor doesnot changes?
(a) Wavelength
(b) Frequency
(c) Velocity
(d) None of these
Answer : B

Question. A magnified real image is formed by a convex lens when the object is at
(a) F
(b) between F and 2F
(c) 2F
(d) only (a) and (b) both

Answer : D

Question. Magnification produced by a rear view mirror fitted in vehicles 
(a) is less than one
(b) is more than one
(c) is equal to one
(d) can be more than or less than one depending upon the position of the object in front of it.

Answer : A

Question. A full length image of a distant tall building can definitely be seen by using 
(a) a concave mirror
(b) a convex mirror
(c) a plane mirror
(d) both concave as well as plane mirror

Answer : B

Question. If the image is formed in front of the mirror, then the image distance will be
(a) positive or negative depending on the size of the object
(b) neither positive nor negative
(c) positive
(d) negative

Answer : D

Question. When light falls on a smooth polished surface, most of it
(a) is reflected in the same direction
(b) is reflected in different directions
(c) is scattered
(d) is refracted into the second medium

Answer : A

Question. A concave mirror of focal length 20 cm forms an image having twice the size of object. For the virtual position of object, the position of object will be at
(a) 25 cm
(b) 40 cm
(c) 10 cm
(d) At infinity

Answer : C

Question. The angle of incidence for a ray of light having zero reflection angle is
(a) 0
(b) 30°
(c) 45°
(d) 90°

Answer : A

Question. A divergent lens will produce
(a) always real image
(b) always virtual image
(c) both real and virtual image
(d) none of these

Answer : B

Question. A ray of light is travelling from a rarer medium to a denser medium. While entering the denser medium at the point of incidence, it
(a) goes straight into the second medium
(b) bends towards the normal
(c) bends away from the normal
(d) does not enter at all

Answer : B

Question. Magnifying power of a concave lens is
(a) always > 1
(b) always < 1
(c) always = 1
(d) can have any value

Answer : B

True and False :

Question. A convex lens (ng = 3/2) when placed in water (nw = 4/3) has increased focal length 
Answer: True

Question. Angle of refraction cannot exceed 90°. 
Answer: True

Question. A convex and a concave lens of equal focal length behaves as a regular glass slab receiving light normally. 
Answer: False

Question. Concave lens and convex mirror diverge the rays which fall parallel to the principal axis.
Answer: True

Question. A person standing in front of a mirror finds his image larger than himself. This shows that mirror is convex in nature. 
Answer: False