Question

A 5 cm tall object is placed perpendicular to the principal axis of a lens of power + 5d.The distance of the object from the lens is 30 cm

Answer 1

Dear Student,

◆ Complete question -

Q. A 5 cm object is placed perpendicular to the principal axis of lens of power +5D the distance of the object from the lens is 30 cm. Find the position, nature and size of the image formed.

● Answer -

Image will be formed at 60 cm on right of size 10 cm and is real, inverted and magnified.

◆ Explaination -

# Given -

P = +5 D

u = -30 cm

h1 = +5 cm

# Solution -

Focal length is -

f = 1/P

f = 1/5

f = 0.2 m

f = 20 cm

According to lens formula -

1/f = 1/v - 1/u

1/20 = 1/v - 1/(-30)

v = +60 cm

Magnification is -

M = -v/u

M = -60/(-30)

M = +2

Size of the image is -

M = h2/h1

2 = h2/5

h2 = 5×2

h2 = 10 cm

So the image will be formed at 60 cm on right of size 10 cm and is real, inverted and magnified.

Thanks dear...

Answer 2

10cm is the correct answer