What magnification will be produced by a lens of power –4.00 D (such as might be used to correct myopia) if an object is held 43 cm away? Your answer should be a number with two decimal places. Hint: you need to first determine the focal distance of the lens.

The magnification is

Explanation:

From the question we are told that

  The  power of the lens is  

Generally  

  The object distance is the negative sign is because the distance is measured in the opposite direction of incident light (i.e away )

 Generally the focal length is mathematically represented as

   =>  

  =>  

converting to  cm  

 =>  

Generally from lens equation  we have that  

=>  

=>  

Generally the magnification is mathematically represented as

=>    

=>