Question

An object 10 cm high is located 80 cm to the left of the first converging lens with focal length 40 cm..A second converging lens with focal length 50 cm is located 150 cm to the right of the first lens. Where is the image formed (to the right of the second lens)? A) 100 cnm B) 140 cm C) 175 cm D) 215 cm

Answer 1

Answer:

image is -175 cm and negative sign show that image is same side of object that is here left to the 2nd lens

Explanation:

given data

focal length f = 40 cm

high = 10 cm

distance u = 80 cm

focal length f = 50 cm

distance u  = 150 cm

to find out

Where is the image formed

solution

we will apply here conversing lens formula that is

1/f = -1/u + 1/v   ......................1

here f is focal length and u and v is distance of object and image

put here all value

1/40 = 1/80 + 1/v

v = 80 cm

so u2 = -150 + v

u2 = -150 + 80

u2 = -70 cm

from equation 1

1/70  + 1/v = 1/50

v = -175 cm

so image is -175 cm

and negative sign show that image is same side of object that is here left to the 2nd lens