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  1. Problems
  2. /Optics
  3. /Lenses and Optical Instruments

Lenses and Optical Instruments

Physics
+ Upload a Problem
More in OpticsReflection of LightRefraction of LightLenses and Optical InstrumentsThe Human Eye and VisionWave OpticsPrisms and Dispersion of LightLight in the Atmosphere
14 problems
Type:
1.
A convex lens of power +6 D is placed in contact with a concave lens of power -2.5 D.
High School (9–10) · Lenses and Optical InstrumentsStemPy LabStemPy Lab
Medium
2.
A doctor prescribes spectacles of power -3.5 D for a student who cannot see distant things clearly.
High School (9–10) · Lenses and Optical InstrumentsStemPy LabStemPy Lab
Medium
3.
Find the power of (a) a convex lens of focal length 80 cm, and (b) a concave lens of focal length…
High School (9–10) · Lenses and Optical InstrumentsStemPy LabStemPy Lab
Easy
4.
A convex lens forms a real image that is 4 times as large as the object.
High School (9–10) · Lenses and Optical InstrumentsStemPy LabStemPy Lab
Hard
5.
A convex lens forms a real image of the same size as the object, on a screen 56 cm from the lens.
High School (9–10) · Lenses and Optical InstrumentsStemPy LabStemPy Lab
Hard
6.
A convex lens of focal length 12 cm is used as a magnifying glass.
High School (9–10) · Lenses and Optical InstrumentsStemPy LabStemPy Lab
Medium
7.
A concave lens has a focal length of 18 cm.
High School (9–10) · Lenses and Optical InstrumentsStemPy LabStemPy Lab
Medium
8.
An object 4 cm tall is placed 32 cm in front of a convex lens of focal length 12 cm.
High School (9–10) · Lenses and Optical InstrumentsStemPy LabStemPy Lab
Medium
9.
A student holds a concave lens of focal length 20 cm, 30 cm from a candle.
High School (9–10) · Lenses and Optical InstrumentsStemPy LabStemPy Lab
Medium
10.
A convex lens is used as a magnifying glass to read small print.
High School (9–10) · Lenses and Optical InstrumentsStemPy LabStemPy Lab
Medium
11.
A camera has a convex lens of focal length 5 cm.
High School (9–10) · Lenses and Optical InstrumentsStemPy LabStemPy Lab
Easy
12.
A student holds a convex lens in sunlight and finds the smallest bright spot on a sheet of paper 21…
High School (9–10) · Lenses and Optical InstrumentsStemPy LabStemPy Lab
Medium
13.
A convex lens has a focal length of 17 cm.
High School (9–10) · Lenses and Optical InstrumentsStemPy LabStemPy Lab
Easy
14.
A parallel beam of light falls on three pieces of glass.
High School (9–10) · Lenses and Optical InstrumentsStemPy LabStemPy Lab
Easy