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Q1. The phenomenon of light bouncing back into the same medium when it strikes a smooth surface is called:
Reflection is the phenomenon in which light rays bounce back into the same medium after striking a smooth surface. Refraction is the bending of light when it passes from one medium to another. Dispersion is the splitting of white light into its constituent colours. Scattering is the spreading of light in different directions. So reflection is correct.
Q2. The type of mirror that always forms a virtual, erect, and diminished image is:
A convex mirror always forms a virtual, erect, and diminished (smaller than the object) image regardless of the position of the object. A plane mirror forms an image of the same size. A concave mirror can form different types of images depending on object position. So convex mirror is correct.
Q3. The point where parallel rays of light meet after reflection from a concave mirror is called the:
The focus (principal focus) of a concave mirror is the point on the principal axis where parallel rays of light converge after reflection. The centre of curvature is the centre of the sphere of which the mirror is a part. The pole is the centre of the reflecting surface. The aperture is the diameter of the reflecting surface. So focus is correct.
Q4. The image formed by a plane mirror is:
A plane mirror always forms a virtual image (cannot be obtained on a screen) that is erect (upright). The image is also of the same size as the object and laterally inverted. It is never real, inverted, or magnified. So virtual and erect is correct.
Q5. The relationship between the angle of incidence and the angle of reflection is:
According to the first law of reflection, the angle of incidence (i) is always equal to the angle of reflection (r). This is a fundamental law of reflection of light. So they are always equal is correct.
Q6. The mirror used by dentists to see an enlarged image of teeth is a:
Dentists use a concave mirror because when the object (tooth) is placed between the focus and the pole, it forms a virtual, erect, and enlarged image. This allows the dentist to see the teeth clearly in detail. A plane mirror does not magnify, and a convex mirror diminishes the image. So concave mirror is correct.
Q7. The spherical mirror whose reflecting surface is curved inwards is called a:
A concave mirror has a reflecting surface that is curved inwards (like the inside of a spoon). It is also called a converging mirror because it converges parallel rays of light. A convex mirror has an outward-curved surface. So concave mirror is correct.
Q8. Which of the following can form a real image?
A concave mirror can form real images (when the object is beyond the focus). A convex mirror always forms virtual images. A plane mirror also always forms virtual images. So only a concave mirror can form a real image among the options. So concave mirror only is correct.
Q9. The center of the spherical mirror’s surface is called the:
The pole (P) is the centre of the reflecting surface of a spherical mirror. The centre of curvature (C) is the centre of the hollow sphere of which the mirror is a part. The focus (F) is where parallel rays meet. The aperture is the diameter of the mirror. So pole is correct.
Q10. The distance from the pole to the focus of a mirror is called the:
The focal length (f) is the distance between the pole (P) and the focus (F) of a spherical mirror. The radius of curvature (R) is the distance between the pole and the centre of curvature. The principal axis is the line passing through the pole and the centre of curvature. So focal length is correct.
Q11. For a spherical mirror, the focal length (f) is related to the radius of curvature (R) by:
For a spherical mirror, the focal length (f) is half of the radius of curvature (R). The relationship is: f = R/2. This is derived from the geometry of spherical mirrors. So f = R/2 is correct.
Q12. The image formed in a convex mirror is always:
A convex mirror always forms a virtual, erect, and diminished image regardless of the object’s position. The image is always formed behind the mirror. It is never real or inverted. So virtual and erect is correct.
Q13. In a concave mirror, when an object is placed at the centre of curvature, the image formed is:
When an object is placed at the centre of curvature (C) of a concave mirror, the image is formed at C itself. The image is real (can be obtained on a screen), inverted (upside down), and of the same size as the object. So real, inverted, and same size is correct.
Q14. The mirror used in solar cookers to concentrate sunlight is a:
Concave mirrors are used in solar cookers because they can concentrate sunlight to a single point (focus), producing high heat. This is due to their converging property. Convex mirrors diverge light, plane mirrors do not concentrate light. So concave mirror is correct.
Q15. The perpendicular line drawn to the reflecting surface at the point of incidence is called the:
The normal is an imaginary line perpendicular to the reflecting surface at the point where the incident ray strikes the surface. It is used to measure the angle of incidence and reflection. The incident ray is the incoming ray, the reflected ray is the outgoing ray. So normal is correct.
Q16. Magnification (m) for a mirror is defined as:
Magnification (m) is the ratio of the size (height) of the image to the size (height) of the object. It is given by: m = hแตข / hโ, where hแตข is the image height and hโ is the object height. So size of image / size of object is correct.
Q17. If magnification (m) is positive for a mirror, the image is:
For a mirror, a positive magnification indicates that the image is virtual and erect (upright). A negative magnification indicates that the image is real and inverted. So virtual and erect is correct.
Q18. Which mirror can produce an image that is both real and virtual depending on object position?
A concave mirror can produce both real and virtual images depending on the position of the object. If the object is beyond the focus, the image is real. If the object is between the focus and the pole, the image is virtual. Plane and convex mirrors always produce virtual images. So concave mirror is correct.
Q19. The reflecting surface of a plane mirror is:
A plane mirror has a flat (plane) reflecting surface. It is not curved inwards (concave) or outwards (convex). The surface is smooth and flat, which is why it produces an image of the same size as the object. So flat is correct.
Q20. Which law states that the incident ray, reflected ray, and normal all lie in the same plane?
The second law of reflection states that the incident ray, the reflected ray, and the normal to the reflecting surface at the point of incidence, all lie in the same plane. The first law states that the angle of incidence equals the angle of reflection. Snell’s law is for refraction. So second law of reflection is correct.
Q21. A virtual image cannot be:
A virtual image is formed by the apparent intersection of reflected (or refracted) rays. It cannot be obtained or projected on a screen because the rays do not actually meet at the image point. It can be seen in a mirror, can be erect, and can be formed by a concave mirror (when object is between pole and focus). So obtained on a screen is correct.
Q22. The mirror used as a shaving mirror is:
A concave mirror is used as a shaving mirror because when the face is placed between the focus and the pole, it forms a virtual, erect, and enlarged image. This magnification helps in seeing finer details while shaving. So concave mirror is correct.
Q23. A ray of light passing through the centre of curvature of a concave mirror, after reflection, will:
A ray of light passing through the centre of curvature (C) of a concave mirror strikes the mirror along the normal (since the radius is perpendicular to the surface at that point). Therefore, it reflects back along the same path, retracing its path. So retrace its path is correct.
Q24. An object is placed between a concave mirror and its focus. The image will be:
When an object is placed between the focus (F) and the pole (P) of a concave mirror, the image formed is virtual, erect, and larger than the object. This is the same situation as the shaving mirror. So virtual and erect is correct.
Q25. For a concave mirror, if the object is at infinity, the image is formed at:
When an object is at infinity (very far away), the rays coming from it are parallel. After reflection from a concave mirror, these parallel rays converge at the focus (F). So the image is formed at the focus. So focus is correct.
Q26. Which mirror is also known as a diverging mirror?
A convex mirror is called a diverging mirror because it diverges (spreads out) parallel rays of light incident on it. A concave mirror is a converging mirror. So convex mirror is correct.
Q27. The rear-view mirrors of cars are usually:
Convex mirrors are used as rear-view mirrors in cars because they provide a wider field of view (they cover a larger area behind the vehicle). Though the images formed are diminished, the wider view is essential for safety. So convex mirrors is correct.
Q28. The radius of curvature for a spherical mirror is the distance between:
The radius of curvature (R) is the distance between the pole (P) and the centre of curvature (C) of a spherical mirror. It is equal to twice the focal length (R = 2f). So pole and centre of curvature is correct.
Q29. The mirror formula is given by:
The mirror formula is 1/f = 1/u + 1/v, where f is the focal length, u is the object distance, and v is the image distance. This formula is valid for both concave and convex mirrors with proper sign conventions. So 1/u + 1/v = 1/f is correct.
Q30. A convex mirror forms the image of an object placed at infinity. Where is the image located?
For a convex mirror, parallel rays (from an object at infinity) appear to diverge from the focus after reflection. The image is formed at the focus, behind the mirror. It is virtual, erect, and highly diminished. So at the focus, behind the mirror is correct.
Q31. The mirror which can form an image larger than the object is:
A concave mirror can form an image larger than the object when the object is placed between the focus and the pole (virtual, erect, enlarged) or between the focus and the centre of curvature (real, inverted, enlarged). A plane mirror gives same size, and a convex mirror gives diminished images. So concave mirror is correct.
Q32. If the image distance (v) is negative in the mirror formula, the image is:
According to the sign convention for mirrors, a negative image distance (v) indicates that the image is virtual and formed behind the mirror. A positive v indicates a real image formed in front of the mirror. So virtual is correct.
Q33. The phenomenon where left appears right and right appears left in a mirror is called:
Lateral inversion is the phenomenon in which the left side of an object appears as the right side in its image formed by a plane mirror, and vice versa. This is why the word “AMBULANCE” is written backwards on vehicles. So lateral inversion is correct.
Q34. Which of the following is not a use of a convex mirror?
Shaving mirrors are concave mirrors, not convex mirrors. Convex mirrors are used in rear-view mirrors, security mirrors in shops, and mirrors at road bends to provide a wider field of view. So shaving mirror is not a use of a convex mirror.
Q35. For a concave mirror, if the object is at the focus, the image is formed at:
When an object is placed at the focus (F) of a concave mirror, the reflected rays are parallel to each other. A parallel beam of light meets at infinity. So the image is formed at infinity. So infinity is correct.
Q36. The image formed by a concave mirror is observed to be virtual, erect, and larger than the object. Where should the object be placed?
A concave mirror forms a virtual, erect, and larger image only when the object is placed between the focus (F) and the pole (P). This is the same as the shaving mirror case. So between focus and pole is correct.
Q37. A ray of light incident on a spherical mirror parallel to its principal axis, after reflection, will pass through:
A ray of light parallel to the principal axis of a concave mirror passes through the focus (F) after reflection. For a convex mirror, it appears to come from the focus behind the mirror. So the focus for a concave mirror is correct.
Q38. The number of images formed when two plane mirrors are placed at an angle of 90 degrees to each other is:
The number of images formed by two plane mirrors at an angle ฮธ is given by n = 360/ฮธ โ 1. For ฮธ = 90ยฐ, n = 360/90 โ 1 = 4 โ 1 = 3. So 3 images are formed. So 3 is correct.
Q39. A convex mirror is preferred over a plane mirror for use as a rear-view mirror because it:
Convex mirrors provide a wider field of view compared to plane mirrors. This allows the driver to see a larger area behind the vehicle, which is important for safety. They do form diminished images, but the wider view is the advantage. So gives a larger field of view is correct.
Q40. If an object is moved towards a concave mirror from infinity, the size of its real image will:
As an object moves from infinity towards the concave mirror, its real image moves from the focus towards the centre of curvature and then beyond. The size of the real image increases as the object approaches the mirror (up to the centre of curvature, where it is same size, and then larger between focus and C). So the size increases. So increase is correct.
Q41. Which mirror will you use to get a beam of parallel light from a source placed at its focus?
A concave mirror is used to get a beam of parallel light from a source placed at its focus. Rays coming from the focus after reflection from a concave mirror become parallel. This principle is used in torch lights, searchlights, and headlights. So concave mirror is correct.
Q42. The focal length of a plane mirror is:
A plane mirror can be considered as a spherical mirror with an infinite radius of curvature (R โ โ). Since f = R/2, f โ โ. So the focal length of a plane mirror is infinity. So infinity is correct.
Q43. A concave mirror produces a real image of an object. The image is of the same size as the object. The object is at:
When an object is placed at the centre of curvature (C) of a concave mirror, the image is formed at C itself. The image is real, inverted, and of the same size as the object. So centre of curvature is correct.
Q44. A ray of light strikes a plane mirror at an angle of 30ยฐ to the normal. The angle of reflection will be:
According to the first law of reflection, the angle of incidence is equal to the angle of reflection. Since the angle with the normal is 30ยฐ, the angle of incidence is 30ยฐ. Therefore, the angle of reflection is also 30ยฐ. So 30ยฐ is correct.
Q45. Which mirror is used in torch lights to direct light in a specific direction?
Concave mirrors are used in torch lights, headlights, and searchlights. A source of light is placed at the focus of the concave mirror, and the reflected rays emerge as a parallel beam, directing light in a specific direction. So concave mirror is correct.
Q46. The magnification produced by a plane mirror is:
A plane mirror forms an image that is of the same size as the object. Therefore, the magnification (m = hแตข/hโ) is equal to 1. It is not less than 1 (that would be diminished) or greater than 1 (that would be magnified). So equal to 1 is correct.
Q47. The mirror that can be used to concentrate sunlight to produce heat is a:
A concave mirror is used to concentrate sunlight to a single point (focus), producing high heat. This is used in solar cookers and solar furnaces. Plane and convex mirrors do not concentrate light. So concave mirror is correct.
Q48. An object is placed at a distance of 15 cm from a concave mirror of focal length 10 cm. The image distance will be:
Using the mirror formula: 1/f = 1/u + 1/v. Here, f = -10 cm (concave mirror, focal length negative by sign convention), u = -15 cm (object distance negative). So 1/v = 1/f โ 1/u = 1/(-10) โ 1/(-15) = -1/10 + 1/15 = (-3 + 2)/30 = -1/30. Therefore, v = -30 cm. The negative sign indicates the image is real and in front of the mirror. The image distance is 30 cm. So 30 cm is correct.
Q49. For a convex mirror, the focal length is taken as:
According to the sign convention for mirrors, the focal length (f) of a convex mirror is taken as positive. This is because the focus of a convex mirror is behind the mirror (virtual focus). For a concave mirror, f is negative. So positive is correct.
Q50. The image formed by a concave mirror is found to be highly magnified and inverted. The object is likely placed:
A concave mirror forms a highly magnified, real, and inverted image when the object is placed between the focus (F) and the centre of curvature (C). At the focus, the image is at infinity. Between pole and focus, the image is virtual and erect. At C, the image is same size. So between focus and centre of curvature is correct.