The crystalline lens of the human eye is a double-convex lens made of material h

Question

The crystalline lens of the human eye is a double-convex lens made of material having an index of refraction of 1.44 (although this varies). Its focal length in air is about 8.00 mm , which also varies. We shall assume that the radii of curvature of its two surfaces have the same magnitude.
(Note: The results obtained in the parts A, B and C are not strictly accurate, because the lens is embedded in fluids having refractive indexes different from that of air.)

Find the radii of curvature of this lens. 7.04mm

If an object 20.0 cm tall is placed 33.0 cm from the eye lens, where would the lens focus it?

How tall would the image be?

Is this image real or virtual?

Is it erect or inverted?

Explanation / Answer

using lens makers formula,

1/f = (n - 1)[1/R1 - 1/R2]

1/8 = (1.44 - 1)(2 / R)

R = 7.04 mm .......Ans

object distance, p = 33 cm

f = 8 mm = 0.8 cm

1/f = 1/p + 1/q

1/0.8 = 1/33 + 1/q

q = 0.82 cm Or 8.2 mm ......Ans

m = - q / p = - 0.82 / 33 = 0.025

hi = m ho = - 0.5 cm ....Ans

q is +ve so real image .....Ans

m is negative so inverted .....Ans

Related Questions

Navigate

• Browse (All)
• Browse T
• Subjects

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