Question

An aeroplane is flying at a height of
1500 m. It has a camera with a lens of
focal length 0.45 m and the
photographic plate is square and of
area 0.09 m2. The area on the ground
that can be photographed at an instant
is
1) 105 m2 2) 106m2
3) 104 m2 4) 103 m

Answer 1

Answer:

option 2 10^6m^2

Explanation:

magnification=hi/ho=v/u

image to form on square plate of hieght =$\sqrt{area}$=0.3m

final image v=uf/u+f

                     =$\frac{-1500*0.45 }{-1500+0.45}$ =approx 0.45

m=v/u=0.45/-1500

  =-$-3*10^{-4}$

AREAL MAGNIFICATION=$(LINEAR MAGNIFICATION)^{2}$

                                          =Ai/Ao

                                          Ao =$\frac{Ai}{m^2} =\frac{0.09}{(3*10^-4)^2}$

                                        =     $10^6m^2$

Answer 2

Answer:

option 2 10^6m^2

Explanation:

magnification=hi/ho=v/u

image to form on square plate of hieght ==0.3m

final image v=uf/u+f

                    = =approx 0.45

m=v/u=0.45/-1500

 =-

AREAL MAGNIFICATION=

                                         =Ai/Ao

                                         Ao =

                                       =