6. Focal length

Find the correct value:
 
An object is placed at \(20\ cm\) infront of a concave lens and forms an image at \(6\ cm\). Find the focal length.
 
Focal length, (\(f\)) \(=\) \(cm\)
 
[Note: Enter the answer upto two decimal places.]
Login or Fast registration
Previous task
Exit to the topic
Next task
Copyright © 2026 YaClass Tech Private Limited Contacts Terms and Conditions Privacy Policy