An object is placed 20cm from …

CBSE, JEE, NEET, CUET

Question Bank, Mock Tests, Exam Papers

NCERT Solutions, Sample Papers, Notes, Videos

An object is placed 20cm from the pole of the convex mirror . If its image is formed 12cm from the mirror,then the focal length of the mirror is ........ ? plz answer quick ☝

Posted by Lalithya Sivakumar 5 years, 4 months ago

CBSE > Class 10 > Science

3 answers

Shruti Trivedi Trivedi 5 years, 4 months ago

F=+30

0Thank You

Ratan Raj 5 years, 4 months ago

F=-30cm

0Thank You

Gaurav Seth 5 years, 4 months ago

Given: A luminous object is placed 20cm from the surface of a convex mirror is set so that the virtual image formed in the two mirror coincide. If the plane mirror is at a distance 12cm from the object

To find the focal length of the convex mirror.

Solution:

As plane mirror is place at a distance of 12 cm from the object, the image formed by plane mirror will be at a distance of 12 cm from the plane mirror as shown in above figure.

AS the virtual image formed by two image coincides, the distance between object and image in both cases is 12+12=24cm as shown in figure.

Given object distance in convex mirror is 20 cm from the convex mirror, so the image will be 4cm (24−20=4) away from the convex mirror, as shown in the figure.

Hence considering convex mirror,

Object distance, u=−20cm

Image distance, v=+4cm

Applying the mirror formula,

1/v + 1/u = 1/f

f = 5 cm

0Thank You

ANSWER

Test

Related Questions

Digestion is begin from in the presence in which enzymes or digestion occur

Posted by Ansh Preet 10 months, 1 week ago

CBSE > Class 10 > Science

1 answers

This content has been hidden. One or more users have flagged this content as inappropriate. Once content is flagged, it is hidden from users and is reviewed by myCBSEguide team against our Community Guidelines. If content is found in violation, the user posting this content will be banned for 30 days from using Homework help section. Suspended users will receive error while adding question or answer. Question comments have also been disabled. Read community guidelines at https://mycbseguide.com/community-guidelines.html

Few rules to keep homework help section safe, clean and informative.

Don't post personal information, mobile numbers and other details.
Don't use this platform for chatting, social networking and making friends. This platform is meant only for asking subject specific and study related questions.
Be nice and polite and avoid rude and abusive language. Avoid inappropriate language and attention, vulgar terms and anything sexually suggestive. Avoid harassment and bullying.
Ask specific question which are clear and concise.

Remember the goal of this website is to share knowledge and learn from each other. Ask questions and help others by answering questions.

Posted by Pandey Ji 5 months, 4 weeks ago

CBSE > Class 10 > Science