Question

(I) From the above table, find the focal length of the lens without using the lens formula.

a) f = 50cm b) f = 30cm c) f = 15cm d) f = 60cm

(ii) Which set of observation is incorrect?

a) Set – 1 b) Set – 2 c) Set – 3 d) Set – 5

(iii) In which case the size of the object and the image will be same?

a) u = 24cm b) u = 60cm c) u = 30cm d) u = 40cm

(iv) Where should Rohit keep the object to get a virtual image?

a) at 30cm b) at 10cm c) at 60cm d) at 15cm

(v) What is the nature and size of the image formed in the case of set – 2?

a) Real, inverted and Enlarged. b) Virtual, erect and enlarged.

c) Real, inverted and diminished. d) virtual, erect and diminished​

Answer 1

iv option is at 10 cm option b

Explanation:

if object distance decreases image size increased