LIGHT-REFLECTION AND REFRACTION

Subject: Physics WORKSHEET 1 Grade: 10

1.A light ray strikes a flat, smooth, reflecting surface at an angle of 80° to the normal. What is
the angle that the reflected ray makes with the surface of the mirror?
2.Light from a laser strikes a plane mirror at an angle of 38° to the normal. If the laser is
moved so that the angle of incidence increases by 13°, what is the new angle of reflection?
3. Two plane mirrors are positioned at right angles to one another. A ray of light strikes one
mirror at an angle of 30° to the normal. It then reflects toward the second mirror. What is
the angle of reflection of the light ray of the second mirror?
4. An object is 36.0 cm in front of a concave mirror with a 16.0-cm focal length. Determine
the image position.
5.A 3.0-cm-tall object is 20.0 cm from a 16.0-cm-radius concave mirror. Determine the image
position and image height.
6.A concave mirror has a 7.0 cm focal length. A 2.4 cm tall object is 16.0 cm from the mirror.
Determine the image height.
7.An object is near a concave mirror of 10.0 cm focal length. The image is 3.0 cm tall,
inverted, and 16.0 cm from the mirror. What are the object position and object height?
8.A convex mirror has a focal length of 13.0 cm. A light bulb with a diameter of 6.0cm is
placed 60.0 cm from the mirror. What is the light bulb’s image position?
9.A convex mirror is needed to produce an image that is three-fourths the size of an object
and located 24 cm behind the mirror. What focal length should be specified?
10.A 7.6-cm-diameter ball is located 22.0 cm from a convex mirror with a radius of curvature
of 60.0 cm. What are the ball’s image position and diameter?
11.A 1.8-m-tall girl stands 2.4 m from a store’s security mirror. Her image appears to be 0.36
m tall. What is the focal length of the mirror?
12.An object is placed 20.0 cm in front of a concave mirror with a focal length of 9.0cm.
What is the magnification of the image? Also predict the nature of the image formed.
13.The placement of an object in front of a concave mirror with a focal length of 12.0cm
forms a real image that is 22.3 cm from the mirror. What is the object position?
14.A convex mirror is used to produce an image that is two-thirds the size of an object and
located 12 cm behind the mirror. What is the focal length of the mirror?
15.How far does the image of a car appear behind a convex mirror, with a focal length of 6.0
m, when the car is 10.0 m from the mirror?
16.4.5 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.
17.It is desired to obtain an erect image of an object, using concave mirror of focal length of
12 cm.
(i)What should be the range of distance of an object placed in front of the mirror?
(ii)Will the image be smaller or larger than the object? Draw ray diagram to show the
formation of image in this case,.
(iii)Where will the image of this object be, if it is placed 6 cm in front of the mirror? Draw ray
diagram for this situation to justify your answer.
Show the position of pole, principal focus and the centre of curvature in the ray diagram.
18.A student has three concave mirrors A, B and C of focal lengths 20 cm, 15 cm and 10 cm
respectively. For each concave mirror he performs the experiment of image formation for
three values of object distance of 30cm, 10 cm and 20 cm.Giving reason answer the
following:
(a)For the three object distances, identify the mirror which will form an image equal in size to
that of object. Find at least one value of object distance.
(b)Out of the three mirrors, identify the mirror which would be preferred to be used for
shaving purpose.
(c)For the mirror B, draw ray diagram for image formation for any two given values of object
distance.
19.List four characteristics of the images formed by plane mirrors
20.When an object is kept within the focus of a concave mirror, an enlarged image is formed
behind the mirror. This image is
(a) real (b) inverted (c) virtual and inverted (d) virtual and erect
21.Name the type of mirrors used in the design of solar furnaces. Explain how high
temperature is achieved by this device.
22. The magnification produced by a spherical mirror is –3”. List four informations you obtain
from this statement about the mirror/image.
23.List two properties of the images formed by convex mirrors. Draw ray diagram in support
of your answer.
24.If the image formed by a spherical mirror for all positions of the object placed in front of it
is always erect and diminished , what type of mirror is it? Draw a labelled ray diagram to
support your answer.
25.List four specific characteristics of the images of the objects formed by convex mirrors.
26. State the two laws of reflection of light.
27. Draw a ray diagram to show the path of the reflected ray corresponding to an incident
ray which is directed towards the principal focus of a convex mirror. Mark on it the angle of
incidence and the angle of reflection.
28. Draw ray diagrams for the following cases when a ray of light : (i) passing through centre
of curvature of a concave mirror is incident on it. (ii) parallel to principal axis is incident on
convex mirror.(iii) is passing through focus of a concave mirror incident on it.
MCQ
1.An object is kept at a distance more than twice the focal length (F) from a concave mirror.
The distance the image formed will be
(a) less then F (b) equal to F (c) between F and 2 F (d) More than 2 F
2.A light ray passing through the centre of curvature is incident on a concave mirror. What will be
the angle of reflection?
(a)00 (b) 450 (c)900 (d)1800
3.Name the mirror that can give an erect and enlarged image of an object?
4.In torches, search lights and head lights of vehicles the bulb is placed
(a) Between pole and focus (b) Very near to the focus
(c) Between focus and centre of curvature (d) At centre of curvature
5.The rays, parallel to the principal axis, of a spherical mirror, actually meet at a point 20 cm
distant from its pole. Identify the mirror and give its focal length.
6. Which type of mirror is usually used as a rear-view mirror in motor cars?
7.The image formed by a concave mirror is observed to be virtual, erect and larger than the
object. Where should be the position of the object?
(a) Between the principal focus and the centre of curvature.
(b) At the centre of curvature
(c) Beyond the centre of curvature
(d) Between the pole of the mirror and its principal focus.
8.A ray of light is incident at angle of 35° to a plane surface. What will the angle of reflection?
(a)550 (b)350 (c)450 (d)900
9.A ray of light is incident on a concave mirror along its principal axis. What will be
the angle of reflection?
(a)550 (b)00 (c)500 (d)900
10.A student conducts an activity using a flask of height 15 cm and a concave mirror. He finds
that the image formed is 45 cm in height. What is the magnification of the image?
(a) -3 times (b) -1/ 3 times (c) 1/ 3 times (d) 3 times
11. A full length of the image of a distant tall building can definitely be seen using:
(a) a concave mirror (b) a convex mirror
(c) a plane mirror (d) both concave as well as plane mirrors
12.Magnification produced by a rearview 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
13.The focal length of a plane mirror is
(a) 0 (b) infinite (c) 25 cm (d) -25 cm
14.An object is placed at a distance of 0.25m infront of a plane mirror. The distance between
the object and image will be
(a) 0.25 m (b) 1.0m (c) 0.5m (d) 0.125m
15.The angle of incidence for a ray of light having zero, reflection angle is
(a) 0 (b) 30° (c) 45° (d) 90°
16.For a real object, which of the following can produce a real image?
(a) Plane mirror (b) Concave mirror (c) Concave lens (d) Convex mirror
17.Which of the following mirror is used by a dentist to examine a small cavity?
(a) Convex mirror (b) Plane mirror
(c) Concave mirror (d) Combination of convex and concave mirror
18.An object at a distance of 30 cm from a concave mirror gets its image at the same point.
The focal length of the mirror is (a) –30cm (b) 30cm (c) –15cm (d) +15cm
19.An object at a distance of +15 cm is slowly moved towards the pole of a convex mirror.
The image will get
(a) shortened and real (b) enlarged and real (c) enlarge and virtual (d) diminished and virtual
20.A concave mirror of radius 30 cm is placed in water. It’s focal length in air and water differ
by
(a)15 (b)20 (c)30 (d)0
21.A concave mirror of focal length 20 cm forms an image having twice the size of the object. For the
virtual position of the image, the position of the object will be at
(a) 25cm (b) 40cm (c) 10cm (d) At infinity
22. The image formed by concave mirror is real, inverted and of the same size as that of
the object. The position of object should be
(a)At the focus (b) at the centre of curvature
(c)Between focus and centre of curvature (d) beyond centre of curvature
23. The nature of the image formed by concave mirror when the object is placed
between the focus (F) and centre of curvature (C) of the mirror observed by us is
(a) real, inverted and diminished (b) virtual, erect and smaller in size
(c) real, inverted and enlarged (d) virtual, upright and enlarged
24. The nature of image formed by a convex mirror when the object distance from the
mirror is less than the distance between pole and focal point (F) of the mirror would be
(a) real, inverted and diminished in size (b) real, inverted and enlarged in size
(c) virtual, upright and diminished in size (d) virtual, upright and enlarged in size