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 8
A lens forms an image that is smaller than the object. What can you say about the position of the object?
A lens has a power of -2 diopters. Is it a convex or concave lens?
A student observes that the image formed by a lens is virtual, erect, and larger than the object. Which lens is being used and where is the object placed?
If a lens forms an image at the same distance as the object but on the opposite side, what is the nature of the lens?
A convex lens has a focal length of 20 cm. What is its power?
A student observes that the image formed by a lens is virtual, erect, and larger than the object. Which lens is being used and where is the object placed?
A student places an object 30 cm from a convex lens of focal length 15 cm. Where will the image be formed?
If a lens forms an image at the same distance as the object but on the opposite side, what is the nature of the lens?
Which lens would you use to magnify a small object?
(1) Concave lens
(2) Convex lens
(3) Plano lens
(4) Cylindrical lens
Which of the following best describes the image formed by a convex lens when the object is placed between the lens and its focus?
(1) Real, inverted, diminished
(2) Virtual, erect, enlarged
(3) Real, erect, enlarged
(4) Virtual, inverted, diminished
Which of the following is a converging lens?
(1) Concave lens
(2) Convex lens
(3) Plano lens
(4) Cylindrical lens
Which of the following is a property of the image formed by a concave lens?
(1) Real and inverted
(2) Virtual and erect
(3) Real and erect
(4) Virtual and inverted
A lens that is thicker at the center than at the edges is called a ________ lens.
A ray of light passing through the center of a lens will ________.
The distance between the optical center and the principal focus of a lens is called the ________.
The formula 1/f = 1/v - 1/u is known as the ________ formula for lenses.
True or False: A concave lens always forms a virtual image.
True or False: A convex lens always forms a real image.
True or False: A lens with a shorter focal length has a higher power.
True or False: The focal length of a lens depends on the material of the lens and the medium in which it is placed.
