Questions
A plane mirror is placed 22.5 cm in front of a concave mirror of focal length 10 cm. Find where an object can be placed between the two mirrors, so that the first image in both the mirrors coincides.
detailed solution
Correct option is B
As shown in figure, if the object is placed at a distance x from the concave mirror, its distance from the plane mirror will be (22.5 - .r). So plane mirror will from equal and erect image of object at a distance (22.5 -x) behind the mirror.Now as according to given problem the image formed by concave mirror coincides with the image formed by plane mirror, therefore for concave mirror v=−22.5+22.5−x=−45−xAnd u−x; 1−45−x+1−x=1−104545x−x2=110; x2−45x+450=0x−30x−15=0 x=30 cm or, x=15 cmBut as the distance between two mirrors is 22.5 cm, x = 30 cm is not admissible. So the object must be at a distance of 15 cm from the concave mirror.Talk to our academic expert!
Similar Questions
The distance of a real object from the focus of a convex mirror of radius of curvature ‘a’ is ‘b’. Then the distance of the image from the focus is
799 666 8865
support@infinitylearn.com
6th Floor, NCC Building, Durgamma Cheruvu Road, Vittal Rao Nagar, HITEC City, Hyderabad, Telangana 500081.
JEE Mock Tests
JEE study guide
JEE Revision Notes
JEE Important Questions
JEE Sample Papers
JEE Previous Year's Papers
NEET previous year’s papers
NEET important questions
NEET sample papers
NEET revision notes
NEET study guide
NEET mock tests