Question

9. Given below are few steps (not in proper sequence)
following in the determination of focal length of a
given convex lens by obtaining a sharp image of a
distant object.
(a) Measures the distance between the lens and
screen
(b) Adjust the position of the lens to form a sharp
image
(c) Selected a suitable distant object
(d) Hold the lens between the object and the screen
with its face parallel to the screen
(a) ca, d. 6
(b) c, d, b,a
(c) c. a, b, d
(d) a, b, c, d​

Answer 1

Answer:

correct option:- (b) c,d,b,a

Explanation:

The correct sequence is below :

(C) Select a suitable distant object, distant object will be considered at infinity.

(D) Hold the lens between object and screen with its faces parallel to the screen, so that rays from object can be converged by lens on screen.

(B) Adjust the position of lens to form a sharp image on screen.

(A) Measure the distance between lens and screen, it will be the focal length of convex lens because image of an object at infinity is always formed on focus.