Delhi Public School Barra
Holidays Homework (Sheet refraction)
Class X
Physics
Q1. What would be angle of incidence for a light ray having zero reflecting angle?
(a) 180° (b) 90° (c) 0° (d) 45°
Q2. To determine the focal length of a concave mirror by forming image of a distant object,
the screen should be placed
(a) in any direction (b) inclined at angle of 45 °
(c) at right angle to the plane of mirror (d) parallel to the plane of mirror
Q3. An object is placed at a distance of 20 cm in front of concave mirror of focal length 10
cm. The image produced is
(a) real, inverted and diminished (b) real, inverted and enlarged
(c) real, inverted and same size (d) virtual, erect and enlarged
Q4. In order to determine focal length of a concave mirror by obtaining the image of distant
object on screen, you need to measure the distance between
(a) mirror and the screen (b) obiect and screen
(c) mirror and object (d) mirror and screen also between object and screen
Q5. Which of the following lens will diverge the ray of light more?
(a) 2D (b) 1D (c) -0.4D (d) -0.8D
Assertion-Reason Questions
Direction (Q.Nos. 6-8) In each of the following questions a statement of Assertion is given by
the corresponding statement of Reason. Of the statements. mark the correct answer as
(a) If both Assertion and Reason are true and Reason is the correct explanation of Assertion.
(b) If both Assertion and Reason are true, but Reason is not the correct explanation of
Assertion.
(c) If Assertion is true, but Reason is false.
(d) If Assertion is false. but Reason is true.
Q6. Assertion (A) ENT specialist use a concave mirror as a head mirror to concentrate light
on the body parts like eye, ear, nose etc.
Reason (R) A concave mirror is more effective and easily available.
Q7. Assertion (A) Keeping a point object fixed, if a plane mirror is moved, the image will also
move.
Reason (R) In case of a plane mirror, distance of object and its image is equal from any point
on the mirror.
Q8. Assertion (A) The speed of light in a rarer medium is greater than that in a denser
medium.
Reason (R) One light year equal to 9.5 x 10¹³ km.
Case Based Source Based Questions
Answer the questions on the basis of your understanding of the following passage and the
related studied concepts
9. The ability of a medium to refract light is expressed in terms of its optical density. Optical
density has a definite connotation. It is not the same as mass density. On comparing two
media, the one with the large refractive index is optically denser medium than the other.
The other medium with a lower refractive index is optically rarer. Also the speed of light
through a given medium is inversely proportional to its optical density.
Holidays Homework (Sheet refraction)
Class X
Physics
Q1. What would be angle of incidence for a light ray having zero reflecting angle?
(a) 180° (b) 90° (c) 0° (d) 45°
Q2. To determine the focal length of a concave mirror by forming image of a distant object,
the screen should be placed
(a) in any direction (b) inclined at angle of 45 °
(c) at right angle to the plane of mirror (d) parallel to the plane of mirror
Q3. An object is placed at a distance of 20 cm in front of concave mirror of focal length 10
cm. The image produced is
(a) real, inverted and diminished (b) real, inverted and enlarged
(c) real, inverted and same size (d) virtual, erect and enlarged
Q4. In order to determine focal length of a concave mirror by obtaining the image of distant
object on screen, you need to measure the distance between
(a) mirror and the screen (b) obiect and screen
(c) mirror and object (d) mirror and screen also between object and screen
Q5. Which of the following lens will diverge the ray of light more?
(a) 2D (b) 1D (c) -0.4D (d) -0.8D
Assertion-Reason Questions
Direction (Q.Nos. 6-8) In each of the following questions a statement of Assertion is given by
the corresponding statement of Reason. Of the statements. mark the correct answer as
(a) If both Assertion and Reason are true and Reason is the correct explanation of Assertion.
(b) If both Assertion and Reason are true, but Reason is not the correct explanation of
Assertion.
(c) If Assertion is true, but Reason is false.
(d) If Assertion is false. but Reason is true.
Q6. Assertion (A) ENT specialist use a concave mirror as a head mirror to concentrate light
on the body parts like eye, ear, nose etc.
Reason (R) A concave mirror is more effective and easily available.
Q7. Assertion (A) Keeping a point object fixed, if a plane mirror is moved, the image will also
move.
Reason (R) In case of a plane mirror, distance of object and its image is equal from any point
on the mirror.
Q8. Assertion (A) The speed of light in a rarer medium is greater than that in a denser
medium.
Reason (R) One light year equal to 9.5 x 10¹³ km.
Case Based Source Based Questions
Answer the questions on the basis of your understanding of the following passage and the
related studied concepts
9. The ability of a medium to refract light is expressed in terms of its optical density. Optical
density has a definite connotation. It is not the same as mass density. On comparing two
media, the one with the large refractive index is optically denser medium than the other.
The other medium with a lower refractive index is optically rarer. Also the speed of light
through a given medium is inversely proportional to its optical density.
