Home
Class 11
PHYSICS
Focal length of a convex lens is 20 cm a...

Focal length of a convex lens is 20 cm and its R.I. is 1.5. It produces an erect, enlarged image if the distance from the object of the lens is

A

40 cm

B

30 cm

C

15 cm

D

20 cm

Text Solution

Verified by Experts

The correct Answer is:
C
Promotional Banner

Topper's Solved these Questions

  • RAY OPTICS

    TARGET PUBLICATION|Exercise EVALUATION TEST|16 Videos

  • RAY OPTICS

    TARGET PUBLICATION|Exercise CRITICALTHINKING|38 Videos

  • OPTICS

    TARGET PUBLICATION|Exercise EXERCISE|447 Videos

  • REFRACTION OF LIGHT

    TARGET PUBLICATION|Exercise EVALUATION TEST|15 Videos

Similar Questions

Explore conceptually related problems

The focal length of a convex lens is 20 cm.What is the power?

Find the focal length of a convex lens which produces a real image at 60 cm from the lens when an object is placed at 40 cm in front of the lens .

Find the focal length of a convex lens which produces a virtual image at 10 cm from the lens when an object is placed at 5 cm from the lens .

A convex lens of focal length f produces a real image 3 times as that of size of the object, the distance between the object and the lens is

The focal length of convex lens is 20 cm. If an object of height 4 cm is placed at a distance of 30 cm from the lens, find: The magnification produced by the lens.

An object is kept at a distance of 60 cm in front of a convex lens. Its real and inverted image is fonned at a distance of 20 cm from the lens. Find the focal length of the lens.

A student measures the focal length of a convex lens by keeping an object pin at a distance u from the lens and measuring the distance v of the image pin. The graph between v versus u plotted will look like

A student measures the focal length of a convex lens by putting an object pin at a distance u from the lens and measuring the distance v of the image pin. The graph between u and v plotted by the student should look like

Read the following paragraph and answer the following questions given below it : Construction of a compound microscope : (i) Acompound microscope consists of a metal tube fitted with two convex lenses at the two ends. These lenses are called the objective lens ( the lens directed towards the object ) and the eyepiece ( the lens directed towards the eye ). Both the lenses are small in size , but the cross section of the objective lens has a short focal length . the focal length of the eyepiece is more than that of the objective lens . (ii) The metal tube is mounted on a stand . thr principal axes of the objective lens and the eyepiece are along the same line . The distance between the object and objective lens can be changed with a screw . It is possible to change the distance between the objective lens and the eyepiece. Working : (i) The object to be observed is illuminated and placed in front of the objective lens. slightly beyond the focal length of the objective lens. it's real , inverted and enlarged image is formed by the objective lens on the other side. (ii) This intermediate image lies with in the focal length of the eyepiece. It serves as an object for the eyepiece. The eyepiece works as a simple microscope . the final image is virtual, highly enlarged and inverted with respect to the original object . It can be formed at the minimum distance of distinct vision from the eyepiece . The final image is observed by keeping the eye close to the eyepiece. Use: This microscope is used to observe blood cells , microorganisms , etc. In a compound microscope , which lens has greater focal length ?

TARGET PUBLICATION-RAY OPTICS-COMPETITIVE THINKING
  1. A poinit object O is placed in front of a glass rod having spherical e...

    Text Solution

    |

  2. A candle placed 25 cm from a lens, forms an image on a screen placed 7...

    Text Solution

    |

  3. Focal length of a convex lens is 20 cm and its R.I. is 1.5. It produce...

    Text Solution

    |

  4. A convex lens (with material of refractive index of 3/2) has two surfa...

    Text Solution

    |

  5. Convex lens made up of glass (mu(g)=1.5) and radius of curvature R is ...

    Text Solution

    |

  6. A convex glass lens (mu(g) = 1.5) has a focal length of 8 cm when plac...

    Text Solution

    |

  7. A double convex thin lens made of glass (refractive index mu = 1.5) h...

    Text Solution

    |

  8. In the figure an air less of raddi of curvature 10 cm (R1 = R2 = 10 cm...

    Text Solution

    |

  9. A plano-convex lens is made of material having refractive index 1.5. T...

    Text Solution

    |

  10. Two identical thin planoconvex glass lenses (refractive index 1.5) eac...

    Text Solution

    |

  11. A thin convex lens made from crown glass (mu=(3)/(2)) has focal length...

    Text Solution

    |

  12. In an optics experiment, with the position of the object fixed, a stud...

    Text Solution

    |

  13. The equiconvex lens has focal length f. If is cut perpendicular to the...

    Text Solution

    |

  14. An equiconvex lens is cut into two halves along (i) XOX' and (ii) YOY'...

    Text Solution

    |

  15. A converging beam of rays in incident on a diverging lens. Having pass...

    Text Solution

    |

  16. Graph of position of image vs position of point object from a convex l...

    Text Solution

    |

  17. Calculate the focal length of a reading glass of a person, if the dist...

    Text Solution

    |

  18. An object is located 4 m from the first of two thin converging lenses ...

    Text Solution

    |

  19. A beam of parallel rays is brought to focus by a planoconvex lens. A t...

    Text Solution

    |

  20. A plano-convex lens fits exactly into a plano-concave lens. Their plan...

    Text Solution

    |