(adsbygoogle = window.adsbygoogle || []).push({}); 1. A rectangular piece of cardboard 21.7cm high is held 1.0m in front of a point source of light. The cardboard is 2.6m away from a wall. How tall is the shadow on the wall?

I have no idea how to do this my prof never talked about this in class and I looked threw the book with no help. I emailed my prof and he told me to google it. The way I thought to do it was to use the b/a=c/d=e/f , and use the ratio of 2.6m/1m = d/.217m and i got d=.56m but it wasn't correct. if any of you guys know how to do this I would greatly appreciate it.

Thanks,

Dblade

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# A Shadow on the Wall

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