1 The projection lens in a certain slide projector is a sing

1. The projection lens in a certain slide projector is a single thin lens. A slide 23.6 mm high is to be projected so that its image fills a screen 1.82 m high. The slide-to-screen distance is 3.06 m.

a.Determine the focal length of the projection lens.

b.How far from the slide should the lens of the projector be placed to form the image on the screen?

2. A jellyfish is floating in a water-filled aquarium 1.38 m behind a flat pane of glass 3.00 cm thick and having an index of refraction of 1.5. (The index of refraction of water is 1.33.)

(a) Where is the image of the jellyfish located? (Find the location of the final image, taking the inside and outside surfaces of the pane of glass as two refracting surfaces. Use a negative number to indicate the image is in the tank. Measure the distance from the air-glass interface. Enter your answer to three decimal places.)

Help please and thank you :)

Solution

here,

let the image distance and the object distance be di and do

magnicication , m = - di/do = hi/ho

- di /do = 1.82 /0.0236 ...(1)

and

di + do = 3.06 ....(2)

from (1) and (2)

di = 3.1 m

do = - 0.04 m

a)

let the focal length be f

using the lens formula

1/f= 1/di + 1/do

1/f = 1/3.1 - 1/0.04

f = -0.04 m

the focal length of the lens is - 0.04 m

b)

the distance between the slide and lens must be 0.04 m