Two converging lenses, A with a focal length of +2.0 cm and Bwith a focal length

Question

Two converging lenses, A with a focal length of +2.0 cm and Bwith a focal length of +5.0 cm, are placed 14 cm apart. An objectis place 3.0 cm to the left of lens A. Determine the position andmagnification of the final image produced by the lens pair: a) bygraphical methods, to scale, with a measurement of the finalposition; and b) by use of the lens equation.

Explanation / Answer

Two converging lenses, A with a focal length of +2.0 cm and B witha focal length of +5.0 cm, are placed 14 cm apart. An object isplace 3.0 cm to the left of lens A. Determine the position andmagnification of the final image produced by the lens pair: a) bygraphical methods, to scale, with a measurement of the finalposition; and b) by use of the lens equation. for the first lens u=3cm f=2cm v=? 1/v=1/f-1/u=1/2-1/3=>v=6cm this image is going to behave as the object for the eyepiece. hence the object distance for the second lens ie eyepiece=14-6=8cm f=5cm so 1/v=1/f-1/u=1/5-1/8=>v=40/3cm hence the final position of the image =40/3cm on the other side ofthe lens. magnification==([40/3]/8 }*6/3=10/3

Related Questions

Navigate

• Browse (All)
• Browse T
• Subjects

---

---

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