Question

solve question 93 plzz

Answer 1

we know, telescope is a combination of two convex lens one have very small aperture then compare to other .
here ,
we put telescope just like two lens put co-axially .

--------------P() ------Q-{} -----------------T

let P and Q are two lens which focal length 5 cm , 200 cm respectively .

T is the building in front of Lens Q
which is known in telescope objective lens . have focal length =200 cm
distance of building from lens =2km
e.g u = 2 km

you can see that
u >> fo
hence, we can say that object placed at infinity distance from mirror .
so, image form in focus of lens Q.
hence,
image distance from lens = 200 cm

now ,

magnification= v/u = 200/200000 = 1/1000

1/1000 = height of image /height of object

1/1000 = height of image /50 m

height of image = 5/100 m = 5cm