Please wait...
1800-212-7858 (Toll Free)
9:00am - 8:00pm IST all days
For Business Enquiry


Thanks, You will receive a call shortly.
Customer Support

You are very important to us

For any content/service related issues please contact on this toll free number


Mon to Sat - 11 AM to 8 PM

A convex lens is placed in contact with a plane mirror. a point object is placed 20cm on the axis of the combination has its image coincideing with itself.what is the focal length of the lens?

Asked by vasturushi 1st February 2018, 9:50 PM
Answered by Expert
The figure shown above describes the problem. If we map the reflected ray in the other side of mirror as the image of mirror, then the ray diagram is same as for the object placed at 2F in front of convex lens. If the object is at 2F of one side of lens, then we get image at 2F of otherside. Since object to lens distance is given as 20 cm in this problem, the focal length of the mirror is 10 cm
Answered by Expert 2nd February 2018, 11:51 AM
Rate this answer
  • 1
  • 2
  • 3
  • 4
  • 5
  • 6
  • 7
  • 8
  • 9
  • 10

You have rated this answer 8/10

Your answer has been posted successfully!

Chat with us on WhatsApp