Question

The the focal length of a convex lens is 50 cm if an object is kept at a distance of 75 cm from lens then find the image distance and magnification produced by the lens

Answer 1

Answer:

v=150

m=2

Explanation:

f=50

u=-75

1/f = 1/v - 1/u

1/50 = 1/v - 1/-75

1/50 + 1/-75 = 1/v

1/50 - 1/75 = 1/v

3-2/150 = 1/v

1/150 = 1/v

Therefore,, v = 150cm...

m= -v/u

m= -150/-75

m = 2.

Hope this helps...

Answer 2

The image distance is 30 cm and the magnification produced by the lens is 0.4

It is given that the focal length (f) of the convex lens is 50 cm.

The object is kept at a distance of (u) 75m from the lens.

According to the Lens formula, we know,

1/f = 1/v - 1/u

⇒ 1/v = 1/f + 1/u

⇒ 1/v = 1/50 + 1/75

⇒ 1/v = 1/30

⇒ v = 30cm

We know, Magnification is given by

M = v/u

Substituting the values, we get

M = 30/75

= 0.4