Class 10 for MCQ Science Chapter 10 Light- Reflection and Refraction
Question 41:
In which of the given cases do we get very strong
reflected rays and very weak refracted rays ?
(a) Light passing from air to
glass
(b) Light passing from water to glass
(c) Light passing from glass to
diamond
(d) Light passing from water to air
Answer
Answer: (d) Light passing from water to air
Question 42:
In order to increase the magnifying power of a
microscope :
(a) The objective
should have larger focal length and eyepiece should have small focal length
(b)
The focal power of the objective and the eyepiece should be larger
(c) The
objective should have small focal length and the eyepiece should have larger focal
length
(d) The focal length of the objective and the eyepiece should be large
Answer
Answer: (a) The objective should have larger focal length and eyepiece should have small focal length
Question 43:
A student does the experiment on tracing the path of
a ray of light passing through a rectangular glass slab for different angles of
incidence. He can get a correct measure of the angle of incidence and the angle of
emergence by following the labelling indicated in figure:
(a) A
(b) B
(c) C
(d) D
Answer
Answer: (d) D
Question 44:
A student traces the path of a ray of light passing
through a rectangular slab for three different values of angle of incidence (∠i )
namely 30o, 45o and 60o. He extends the
direction of incident ray by a dotted line and measures the perpendicular distance
‘l’ between the extended incident ray and the emergent ray.
He will observe that:
(a) ‘l’ keeps on increasing with increase in angle of
incidence
(b) ‘l’ keeps on decreasing with increase in angle of incidence
(c)
‘l’ remains the same for all three angles of incidence
(d) ‘l’ is the maximum for
∠i = 45o and is less than this value for ∠i =
30o and ∠i = 60o.
Answer
Answer: (a) ‘l’ keeps on increasing with increase in angle of incidence
Question 45:
The image which is formed behind the mirror
(a)
real image
(b) virtual image
(c) blue image
(d) partial image
Answer
Answer: (b) virtual image
Question 46:
Convex lens is also known as
(a) converging
lens
(b) diverging lens
(c) radial lens
(d) axial lens
Answer
Answer: (a) converging lens
Question 47:
Using a convex lens, a clear image of candle flame
is produced on a screen. How many other clear images can be received on this screen
if only the lens is to be shifted ?
(a) A large number
(b) Only one
more
(c) Two more
(d) None of these
Answer
Answer: (b) Only one more
Question 48:
A parallel beam of light is incident on a converging
lens parallel to its principal axis. As we move away from the lens on the other side
on its principal axis the intensity of light
(a) Remains constant
(b)
Continuously increases
(c) Continuously decreases
(d) First increases and then
decreases
Answer
Answer: (d) First increases and then decreases
Question 49:
Four students A, B, C and D performed the experiment
to determine the focal length of a concave mirror by obtaining the image of a
distant tree on a screen. They measured the distances between the screen and the
mirror as shown in the diagrams given below:
The correct way to measure accurate focal length of the mirror is:
(a) A
(b)
B
(c) C
(d) D
Answer
Answer: (c) C
Question 50:
A student traces the path of a ray of light passing
through a rectangular slab.
For measuring the angle of incidence, he must position the protractor in the manner
shown in the figure:
(a) A
(b) B
(c) C
(d) D
Answer
Answer: (d) D
Question 51:
While performing an experiment on determination
of focal length of a convex lens, four students obtained the image of the same
distant tree on the screen as follows:
Which diagram shows the formation of image correctly?
(a) A
(b) B
(c)
C
(d) D
Answer
Answer: (d) D
Question 52:
The deviation of light ray from its path when it
travels from one transparent medium to another transparent medium is
called
(a) reflection
(b) refraction
(c) dispersion
(d) scattering
Answer
Answer: (b) refraction
Question 53:
The laws of reflection hold good for
(a)
plane mirror only
(b) concave mirror only
(c) convex mirror only
(d)
all mirrors irrespective of their shape
Answer
Answer: (d) all mirrors irrespective of their shape
Question 54
The mirror used as rear-view
mirror in vehicles
(a) convex mirror
(b) plane mirror
(c) cylindrical
mirror
(d) concave mirror
Answer
Answer: (a) convex mirror
Question 55:
You are given water, mustard oil, glycerine and
kerosene. In which of these media a ray of light incident obliquely at same
angle would bend the most?
(a) Kerosene
(b) Water
(c) Mustard
oil
(d) Glycerin
Answer
Answer: (d) Glycerin
Question 56:
When white light moves through vacuum :
(a)
Violet has greater speed than red
(b) Red has greater speed than
violet
(c) All colors have the same speed
(d) Different colors have
different random speeds
Answer
Answer: (d) (c) All colors have the same speed
Question 57:
Magnifying power of a compound microscope is the
ratio of the angle formed by the final image to the angle formed by the object
when :
(a) Image is at the least distance of distinct vision and object may
be anywhere
(b) Object and image are both at infinity
(c) Object and image
are both at the least distance of distinct vision
(d) Object is placed at the
least distance of distinct vision and image may be at any place
Answer
Answer: (d) Object is placed at the least distance of distinct vision and image may be at any place
Question 58:
Spherical air bubble in water will act as
:
(a) A concave lens
(b) A convex lens
(c) Plane-concave lens
(d)
Plane glass plate
Answer
Answer: (a) A concave lens
Question 59:
A child is standing in front of a magic mirror.
She finds the image of her head bigger, the middle portion of her body of the
same size and that of the legs smaller. The following is the order of
combinations for the magic mirror from the top.
(a) Plane, convex and
concave
(b) Convex, concave and plane
(c) Concave, plane and convex
(d)
Convex, plane and concave
Answer
Answer: (c) Concave, plane and convex
Question 60:
A student used a device (X) to obtain focus the image of a well illuminated
distant building on a screen (S) as shown alongside in the diagram. Select
the correct statement about the device (X).
(a) This device is a concave
lens of focal length 8 cm.
(b) This device is a convex mirror of focal
length 8 cm.
(c) This device is a convex lens of focal length 4
cm.
(d) This device is a convex lens of focal length 8 cm.
Answer
Answer: (d) This device is a convex lens of focal length 8 cm.