Question

an object 45 cm from a lens gave a virtual image at a distance of 15 cm in front of the lens what is the focal length of lens what type of lens is it

Answer 1

u= -45 cm

v = 15 cm 

1/f = 1/v - 1/u 

1/f = 1/15 + 1/45 

1/f = 3 + 1/45

45 = 4f 

f = 45/4 

f = 11.2 cm

Answer 2

yHEYA!!

U= -45

V= 15

MIRROR FORMULA = 1/f = 1/v- 1/u

1/f = 1/v - 1/u

1/f = 1/-45 - 1/15

1/f = 3+ 1/45

4f = 45

f = 45/4

f = 11.2

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