Lenses
Physics ⇒ Light and Optics
Lenses starts at 8 and continues till grade 12.
QuestionsToday has an evolving set of questions to continuously challenge students so that their knowledge grows in Lenses.
How you perform is determined by your score and the time you take.
When you play a quiz, your answers are evaluated in concept instead of actual words and definitions used.
See sample questions for grade 12
A lens forms an image that is diminished, virtual, and upright. What type of lens is it?
A lens forms an image that is real, inverted, and smaller than the object. Where is the object placed relative to a convex lens?
A lens is used to correct hypermetropia (farsightedness). What type of lens is it?
A person uses a lens of power -3 D to correct their vision. What type of lens is this?
A thin lens produces an image twice the size of the object and on the same side as the object. What is the nature of the image?
Describe what is meant by the term 'optical center' of a lens.
Explain the difference between a real and a virtual image formed by a lens.
Explain why chromatic aberration occurs in lenses.
If a lens forms an image at infinity, where must the object be placed?
Which of the following best describes the image formed by a concave lens?
(1) Real, inverted, and magnified
(2) Virtual, upright, and diminished
(3) Real, upright, and diminished
(4) Virtual, inverted, and magnified
Which of the following is a converging lens?
(1) Concave lens
(2) Convex lens
(3) Plano-concave lens
(4) Biconcave lens
Which of the following is NOT a use of lenses?
(1) Magnifying glasses
(2) Telescopes
(3) Electric circuits
(4) Cameras
Which of the following is true for the principal axis of a lens?
(1) It passes through the optical center and is perpendicular to the lens surfaces
(2) It is parallel to the lens surfaces
(3) It is the axis along which light does not bend
(4) It is the axis along which the lens is thickest
The focal length of a lens is the distance from the _______ to the principal focus.
The lens maker's formula is used to calculate the _______ of a lens based on its radii of curvature and refractive index.
The magnification produced by a lens is given by the ratio of _______ to _______.
The power of a lens is measured in _______.
A real image formed by a lens is always inverted. True or false?
If the refractive index of the surrounding medium is greater than that of the lens, the lens behaves as a diverging lens. True or false?
The sign convention for the focal length of a convex lens is positive. True or false?
