At what distance from a simple microscope must an object ...
At what distance from a simple microscope must an object be placed so that the image 5 times the size of the object is produced 20cm from the lens?
2cm
3.3cm
4cm
5cm
15cm
Correct answer is C
M=\(\frac {v}{u}=5\Rightarrow v=5u=20,let u be x\\ v=5x if v=20 then 5x=20 therefore x=20/5=4\,u=4cm\)
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