Home › ICSE Class 10 › physics › Refraction through a Lens › Which is the principal use of a concave lens?
Which is the principal use of a concave lens?
ACameras in the standard view
BSolar furnaces
CSpectacles for myopia
DBurning glass
Answer & Solution
Correct answer: C. Spectacles for myopia
1. Myopia is corrected by lenses with negative power.
2. Concave lenses have negative power and diverge incoming rays.
3. They effectively shift the far point back to infinity.
4. So myopia is corrected using concave spectacles.
5. The other uses listed need converging (convex) lenses.
_Source: Selina Concise Physics ICSE Class 10, Ch 5 'Refraction through a Lens' (aplustopper.com extract)_
Related questions
Linear magnification produced by a converging lens for an object at 2F is:Cross-section of a convex lens looks like:Two lenses of powers +3 D and -5 D are placed in contact. The combination:A virtual image:Image formed by a convex lens with object at infinity is:If both surfaces of a thin lens have equal radii of curvature R, the lens is called:An object is placed beyond 2F from a convex lens. Image position is:If the focal length of a convex lens is doubled, its power: