Question
What is the focal length of a double convex lens for
which the radius of curvature of each surface is 30 cm and the refractive index of glass is 2.50 ?Solution
Here given Surface curvature (R ) = 30 cm., Refractive index (n) = 2.50 For a double convex lens, R = −1R1 1/f = (n-1) {1/(R1 - R2)} => 1/f = (2.5 - 1) {1/30 + 1/30} => 1/f = 1/10 => f = 10 cm Hence, the focal length of a double convex length is 10 cm.
Read the following paragraph.
The importance of education and learning has been recognised since the beginning of time. Education means o lot ...
Which of the given figures when placed in the 5th position would continue the series that is established by the first four figures?
There is a family of six members. There are two married couples. X is a daughter of F, who has two children. F is the mother of Y. Y is the husband of ...
Select the option that is related to the fifth letter-cluster in the same way as the second letter-cluster is related to the first letter-cluster and th...
In a certain code language,
A # B means A is the sister of B.
A @ B means A is the son of B.
A & B means A is the wife of B.
Select the correct mirror image of the given figure, when the mirror is placed at line MN as shown.
Select the set in which the numbers are related in the same way as are the numbers of the following sets.
(NOTE: Operations should be performed o...
The sentence below has a word in which the letters are jumbled up. Rearrange the letters of that word, written in capital letters, to form the correct w...
Which figure should replace the question mark (?) if the following figure series were to be continued?
What should come in place of the question mark (?) in the given series?
13, 22, 33, 46, 7, 78, 97
Relevant for Exams:
