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anomalocaris
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Homework Statement
A real object is placed 9.00 cm from a converging lens that has a focal length of 24.0 cm. The image is________.
My classmate answered "14.4 cm from the lens, virtual, and enlarged," but apparently this is incorrect. I solved it out and chose the option "14.4 cm from the lens, real, and enlarged," though I believe the image should be virtual since my "q" value was negative/<0. I do not have the correct answer since this assignment is still active, so I would really like to understand if I'm taking the wrong steps before my final next week. Any suggestions would be very much appreciated!
Homework Equations
[itex]\frac{1}{f}[/itex] = [itex]\frac{1}{p}[/itex] + [itex]\frac{1}{q}[/itex]
where f=focal distance=24.0 cm
p=distance of real object from the mirror=9.0cm
q=distance of image from the mirror
I also know that f>0 for a converging lens and when q>0, the image will be real.
The Attempt at a Solution
[itex]\frac{1}{24.0 cm}[/itex] = [itex]\frac{1}{9.0 cm}[/itex] + [itex]\frac{1}{q}[/itex]
and so moving things around: [itex]\frac{1}{24.0 cm}[/itex] - [itex]\frac{1}{9.0 cm}[/itex] = [itex]\frac{1}{q}[/itex]
[itex]\frac{1}{q}[/itex]=-[itex]\frac{5}{72}[/itex]
q=(-[itex]\frac{5}{72}[/itex] )^-1 =-14.4
My q is negative, so it should virtual, but irregardless, the computer finds this answer unfit! I'm still a little confused at knowing if it will be enlarged or not, especially because no heights were given for the object.
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