Preparing for exams is always a challenge, but using the right resources can make the process much smoother. Multiple Choice Questions (MCQs) are a crucial part of the CBSE Class 10 Science curriculum, especially in the chapter on Light. Practicing MCQs not only helps you understand the concepts better but also improves your speed and accuracy in answering questions. This article will guide you through the key concepts of the Light chapter and provide a collection of essential MCQ on light class 10 to enhance your preparation.
Key Concepts Covered in Light Chapter
Reflection of Light
Reflection of light is a fundamental concept in physics that explains how light bounces off surfaces. When light hits a smooth surface like a mirror, it reflects at the same angle at which it strikes the surface. This principle is known as the Law of Reflection. Understanding this concept is essential as it forms the basis for various optical devices like periscopes and kaleidoscopes.
MCQ on light class 10 on Reflection of Light
- When a plane mirror is rotated through a certain angle, the reflected ray turns through:
- (a) the same angle
- (b) twice the angle
- (c) half the angle
- (d) none of these
- Answer: (b) twice the angle
- The image formed by a plane mirror is:
- (a) real, inverted, and same size
- (b) virtual, erect, and same size
- (c) virtual, inverted, and smaller
- (d) real, erect, and larger
- Answer: (b) virtual, erect, and same size
- If an object is placed symmetrically between two plane mirrors inclined at an angle of 90 degrees, the number of images formed is:
- (a) 2
- (b) 3
- (c) 4
- (d) 5
- Answer: (c) 4
- The focal length of a plane mirror is:
- (a) zero
- (b) infinite
- (c) 25 cm
- (d) -25 cm
- Answer: (b) infinite
- A real image is formed by a concave mirror when the object is placed:
- (a) between the pole and the focus
- (b) at the focus
- (c) between the focus and the center of curvature
- (d) beyond the center of curvature
- Answer: (c) between the focus and the center of curvature
- The laws of reflection hold good for:
- (a) plane mirrors only
- (b) concave mirrors only
- (c) convex mirrors only
- (d) all types of mirrors
- Answer: (d) all types of mirrors
- In a plane mirror, the distance of the image behind the mirror is equal to:
- (a) the distance of the object from the mirror
- (b) half the distance of the object from the mirror
- (c) twice the distance of the object from the mirror
- (d) zero
- Answer: (a) the distance of the object from the mirror
- A beam of light incident on a plane mirror forms a real image on reflection. The incident beam is:
- (a) parallel
- (b) convergent
- (c) divergent
- (d) none of these
- Answer: (b) convergent
- The image formed by a concave mirror when the object is at infinity is:
- (a) virtual, erect, and diminished
- (b) real, inverted, and highly diminished
- (c) virtual, inverted, and highly diminished
- (d) real, erect, and highly magnified
- Answer: (b) real, inverted, and highly diminished
- When light is incident on a surface at the critical angle, the angle of refraction is:
- (a) 0 degrees
- (b) 45 degrees
- (c) 90 degrees
- (d) equal to the angle of incidence
- Answer: (c) 90 degrees
Refraction of Light
Refraction is the bending of light as it passes from one medium to another of different density. This change in direction occurs because light travels at different speeds in different media. Understanding refraction is crucial for studying lenses and other optical instruments. Here are MCQ on light class 10 refraction of light.
MCQs on Refraction of Light
- When light passes from air into glass, it:
- (a) speeds up
- (b) slows down
- (c) remains unchanged
- (d) none of these
- Answer: (b) slows down
- The refractive index of a medium is the ratio of:
- (a) speed of light in vacuum to speed of light in the medium
- (b) speed of light in the medium to speed of light in vacuum
- (c) wavelength of light in vacuum to wavelength of light in the medium
- (d) frequency of light in vacuum to frequency of light in the medium
- Answer: (a) speed of light in vacuum to speed of light in the medium
- A ray of light passing through the center of curvature of a concave mirror:
- (a) passes through the focus
- (b) is reflected back along the same path
- (c) passes through the pole
- (d) none of these
- Answer: (b) is reflected back along the same path
- If the refractive index of glass relative to air is 1.5, then the speed of light in glass is:
- (a) equal to the speed of light in air
- (b) 1.5 times the speed of light in air
- (c) 0.67 times the speed of light in air
- (d) none of these
- Answer: (c) 0.67 times the speed of light in air
- Which of the following statements is true for the refraction of light?
- (a) The angle of incidence is always equal to the angle of refraction
- (b) The angle of incidence is always greater than the angle of refraction
- (c) The angle of incidence is always less than the angle of refraction
- (d) The ratio of the sine of the angle of incidence to the sine of the angle of refraction is constant
- Answer: (d) The ratio of the sine of the angle of incidence to the sine of the angle of refraction is constant
- The critical angle for total internal reflection for a ray of light passing from glass to air is:
- (a) 30 degrees
- (b) 45 degrees
- (c) 60 degrees
- (d) depends on the wavelength of light
- Answer: (b) 45 degrees
- A convex lens forms a virtual, erect, and magnified image when the object is placed:
- (a) at the focus
- (b) between the lens and the focus
- (c) beyond the focus
- (d) at infinity
- Answer: (b) between the lens and the focus
- The power of a lens is -2D. What is the focal length of the lens?
- (a) +50 cm
- (b) -50 cm
- (c) +100 cm
- (d) -100 cm
- Answer: (b) -50 cm
- A ray of light is incident obliquely on a surface separating two media. The refracted ray:
- (a) bends towards the normal
- (b) bends away from the normal
- (c) travels along the surface
- (d) does not change its path
- Answer: (a) bends towards the normal
- The image formed by a concave lens is always:
- (a) real, inverted, and diminished
- (b) virtual, erect, and diminished
- (c) virtual, erect, and magnified
- (d) real, inverted, and magnified
- Answer: (b) virtual, erect, and diminished
Spherical Mirrors and Lenses
Understanding spherical mirrors and lenses is crucial for mastering the concepts of light. Spherical mirrors are mirrors with curved surfaces, which are either concave (curved inward) or convex (curved outward). These mirrors form images based on the principles of reflection. Lenses, on the other hand, are transparent objects with curved surfaces that refract light to form images. Lenses can be either convex (converging) or concave (diverging).
Image Formation by Spherical Mirrors
Concave mirrors can form real and virtual images depending on the position of the object relative to the mirror’s focal point and center of curvature. Convex mirrors, however, always form virtual, erect, and diminished images. Understanding the ray diagrams for these mirrors helps in predicting the nature, position, and size of the images formed.
MCQ on light class 10 on Spherical Mirrors
- The focal length of a concave mirror is:
- (a) positive
- (b) negative
- (c) zero
- (d) infinite
- Answer: (b) negative
- A convex mirror always forms an image that is:
- (a) real and inverted
- (b) real and erect
- (c) virtual and erect
- (d) virtual and inverted
- Answer: (c) virtual and erect
- The mirror used in vehicles as a rear-view mirror is:
- (a) concave mirror
- (b) convex mirror
- (c) plane mirror
- (d) parabolic mirror
- Answer: (b) convex mirror
- For a concave mirror, if the object is placed at the center of curvature, the image formed is:
- (a) at infinity
- (b) virtual and erect
- (c) at the focus
- (d) real, inverted, and same size as the object
- Answer: (d) real, inverted, and same size as the object
- Which mirror can produce a real and inverted image of the same size as the object?
- (a) Concave mirror
- (b) Convex mirror
- (c) Plane mirror
- (d) None of these
- Answer: (a) Concave mirror
- The image formed by a convex mirror when the object is placed at infinity is:
- (a) real, inverted, and diminished
- (b) virtual, erect, and highly diminished
- (c) real, erect, and same size
- (d) virtual, inverted, and magnified
- Answer: (b) virtual, erect, and highly diminished
- A concave mirror forms a virtual image when the object is placed:
- (a) at infinity
- (b) beyond the center of curvature
- (c) between the focal point and the mirror
- (d) at the center of curvature
- Answer: (c) between the focal point and the mirror
- The radius of curvature of a spherical mirror is:
- (a) twice the focal length
- (b) half the focal length
- (c) equal to the focal length
- (d) four times the focal length
- Answer: (a) twice the focal length
- A virtual, erect, and magnified image is formed by a concave mirror when the object is placed:
- (a) between the focal point and the center of curvature
- (b) at the focal point
- (c) between the mirror and the focal point
- (d) beyond the center of curvature
- Answer: (c) between the mirror and the focal point
- The image formed by a concave mirror when the object is at the focus is:
- (a) real and inverted
- (b) virtual and erect
- (c) highly magnified and real
- (d) at infinity
- Answer: (d) at infinity
Image Formation by Lenses
Lenses are crucial in the study of light as they form images by refraction. A convex lens can produce real and virtual images depending on the object’s position. A concave lens always forms virtual, erect, and diminished images. Understanding lens formulae with MCQ on light class 10 and ray diagrams is essential for predicting image characteristics.
MCQs on Lenses
- A convex lens forms a real, inverted, and same size image when the object is placed:
- (a) at the focus
- (b) at 2F (twice the focal length)
- (c) between the lens and the focus
- (d) beyond 2F
- Answer: (b) at 2F
- The focal length of a concave lens is:
- (a) positive
- (b) negative
- (c) zero
- (d) infinite
- Answer: (b) negative
- The power of a convex lens with a focal length of 50 cm is:
- (a) +2D
- (b) -2D
- (c) +0.5D
- (d) -0.5D
- Answer: (a) +2D
- A concave lens always forms an image that is:
- (a) real, erect, and diminished
- (b) virtual, erect, and diminished
- (c) virtual, inverted, and magnified
- (d) real, inverted, and magnified
- Answer: (b) virtual, erect, and diminished
- When light passes through a convex lens, parallel rays converge at:
- (a) the optical center
- (b) the focus
- (c) the center of curvature
- (d) twice the focal length
- Answer: (b) the focus
- A convex lens forms a virtual and magnified image when the object is placed:
- (a) at the focus
- (b) between the lens and the focus
- (c) at 2F
- (d) beyond 2F
- Answer: (b) between the lens and the focus
- The power of a lens is defined as:
- (a) the reciprocal of the focal length in meters
- (b) the focal length in centimeters
- (c) the radius of curvature
- (d) none of these
- Answer: (a) the reciprocal of the focal length in meters
- If the power of a lens is -4D, the lens is:
- (a) a convex lens
- (b) a concave lens
- (c) a cylindrical lens
- (d) a plane mirror
- Answer: (b) a concave lens
- A magnifying glass is an example of:
- (a) concave lens
- (b) convex lens
- (c) plane mirror
- (d) concave mirror
- Answer: (b) convex lens
- The image formed by a convex lens when the object is placed at infinity is:
- (a) real, inverted, and highly diminished
- (b) virtual, erect, and magnified
- (c) real, erect, and same size
- (d) virtual, inverted, and diminished
- Answer: (a) real, inverted, and highly diminished
Wrapping Up
Mastering the chapter on Light through consistent practice of Multiple Choice Questions (MCQs) is crucial for Class 10 Science students. The key concepts of reflection, refraction, and image formation by mirrors and lenses form the foundation of this chapter. Regular practice with MCQ on light class 10 not only reinforces these concepts but also enhances problem-solving skills and exam readiness. By following a structured study plan and utilizing multiple resources, you can significantly improve your performance and achieve a higher score in your exams.
Remember, consistent practice and thorough understanding of the concepts are the keys to success. Good luck with your preparations!