Aconverging lens of focal length 0.18 m is used to produce an image of an object on a screen. if a magnification of 9.0 x is required, calculate the distance from the object at which the screen must be placed.

distance between object and screen is 2 m

Explanation:

given data

focal length = 0.18 m

magnification = 9.0 x

to find out

distance from the object

solution

we know that magnification is express as

magnification m =   .............1

here u is distance of object from lens

and v is distance of image from lens

so here

9 =

v = 9 u   ..................2

now we will apply here lens formula that is

       ....................3

put here value f is focal length and v = 9 u

solve it we get

u = 0.2

so v = 9 (0.2 )

v = 1.8

so here distance between object and screen is v +u

distance between object and screen = 1.8 + 0.2

distance between object and screen is 2 m

what experimental evidence led scientists to change from the previous model to this one?

a few of the positive particles aimed at a gold foil seemed to bounce back.

the colors of light emitted from heated atoms had very specific energies.

experiments with water vapor showed that elements combine in specific proportions.

cathode rays were bent in the same way whenever a magnet was brought near them.