A converging lens has a focal length of 19 cm. How far from the lens should an o

Question

A converging lens has a focal length of 19 cm. How far from the lens should an object be placed to get a real image with a magnification of 3.4 and a virtual image with a magnification of 3.4?

please help

A converging lens has a focal length of 19 cm. How far from the lens should an object be placed to get a real image with a magnification of 3.4 and a virtual image with a magnification of 3.4? (a) a real image with a magnification of 3.4cm (b) a virtual image with a magnification of 3.4 please help

Explanation / Answer

Magnification of the converging lens is given by

M = -i/o

i = image distance

o = object distance

and equation of lens is

1/f = 1/o + 1/i

given,

f = 19

M = 3.4

multiplying lens equation by o

o/f = 1 + o/i

o/f = 1 - 1/M

since in converging lens vitual image will be erect so magnification will be positive

and for real image will be inverted so magnification will be negative

for real image

o/19 = 1 -(-1/3.4)

o = 21.93 cm

object be placed at 21.93 cm to get real image with magnification of 3.4

for virtual image

o/19 = 1 - 1/3.4

o = 13.4 cm

object be placed at 13.4 cm to get virtual image with magnification of 3.4

Related Questions

Navigate

• Browse (All)
• Browse A
• Subjects

---

---

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.