I got a few simpel questions dealing with and electric field and and "optics" question(adsbygoogle = window.adsbygoogle || []).push({});

OK for the electric field we have an object that is out in space. THe max strength of the electric field form the communications tranmissions are 6.8E-10. THe first part of the questiona tell us that the radio recieving dish is 900m^2. We are to find the average power incident on the dish. The second part asks us to find the max strength of the magnetic field for this. For the first part of the question I was going to use the equation I = Eo*Bo/2Uo, and for some reason i can't get it to work. For the second part i was going to use E= cB but again, no luck.

For the second problem there is a lake with a width of 26M. You are staind 3M away from the lake and your eyes are 1.6M above the ground. There a a tree on the other side of the lake, and from your point of view u can only see the top of the tree's reflection in the lake. They want me to find out how tall the tree is. What i did is draw this picture and then draw my rays of the image from the lake to the tree, and then to me. This game me two triangles.( of which one I knew two sides. After figureing out the 3rd side for one of them i went to work on the second one. Yet again i couldn't figure out the height of the tree. I know i am doing something stupid.

Thanks for the help.

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# Homework Help: Electric Field and Optics questions

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