An object placed on ameter scale at 8 cm mark was focused on a white screen placed at 92 cm mark,using a converginglens placed on the meter scale at 50 cm mark.
a) find the focal length of the converging lens
b) find the position of the image formed if the object is shifted towards the lens at a position of 29 cm
c) state the nature of image formed if the object is further shifte towards the lens.
Asked by rs1702 | 7th Jan, 2019, 12:09: PM
As per our policy one question is going to answered in one url
For this setup
It's given after sign convention
u= infinity
v= -42--
From lens formula
1/v-1/u = 1/f
Putting the values
1/f = 1/42
So focal length of the lens is 42 cm.
Answered by Ankit K | 7th Jan, 2019, 03:11: PM
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