Use app×
Join Bloom Tuition
One on One Online Tuition
JEE MAIN 2025 Foundation Course
NEET 2025 Foundation Course
CLASS 12 FOUNDATION COURSE
CLASS 10 FOUNDATION COURSE
CLASS 9 FOUNDATION COURSE
CLASS 8 FOUNDATION COURSE
0 votes
1.3k views
in Physics by (91.3k points)
closed by
Two lenses of power 15D and -3D are placed in contact. The focal length of the combination is a
A. 10cm
B. 15cm
C. 12cm
D. 18cm

1 Answer

0 votes
by (91.4k points)
selected by
 
Best answer
Correct Answer - D
`"Given" P_(1)=15D and P_(2)=-3D`
`therefore P=P_(1)+P_(2)=15D-3D=12D `
`therefore P=(1)/(f(m)) Rightarrow P=(100)/(f(cm)) Rightarrow 12=(100)/(f)`
Focal length of the combination, `f=(100)/(12)=8.33cm`

Welcome to Sarthaks eConnect: A unique platform where students can interact with teachers/experts/students to get solutions to their queries. Students (upto class 10+2) preparing for All Government Exams, CBSE Board Exam, ICSE Board Exam, State Board Exam, JEE (Mains+Advance) and NEET can ask questions from any subject and get quick answers by subject teachers/ experts/mentors/students.

Categories

...