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What's the length of the spike. Please I really need this helpA cylindrical tower 7.5m high is surmounted by a dome 6m in diameter, on the top of which is a spike. A boy whose eye is 1.5m from the ground can just see the tip of the spike over the curve of the dome when his line of sight is at an elevation of 40°.Calculate the length of the spike and the distance the boy is from the nearest point of the tower. #2 20050402 07:41:00
Re: What's the length of the spike. Please I really need this helpEgads and Gazooks! Give me a coupla days! "The physicists defer only to mathematicians, and the mathematicians defer only to God ..."  Leon M. Lederman #3 20050404 20:38:18
Re: What's the length of the spike. Please I really need this helpBecause the circle sits at eyelevel, and also has the 40° line grazing its upper surface, then a line at 20° (half of 40°) would go thru the circles center. "The physicists defer only to mathematicians, and the mathematicians defer only to God ..."  Leon M. Lederman #4 20050421 22:25:28
Re: What's the length of the spike. Please I really need this helpUnless I'm mistaken you seem to have missed what the problem is asking. #5 20050421 23:06:25
Re: What's the length of the spike. Please I really need this helpThank you. I did not mean that his line of sight passed through the very top, I merely said "grazes the upper surface" (ie a tangent) "The physicists defer only to mathematicians, and the mathematicians defer only to God ..."  Leon M. Lederman #6 20050830 04:33:20
Re: What's the length of the spike. Please I really need this helpWhen I give my answer below as the distance to the column, I am assuming that the dome fits perfectly on the column, Pages: 1 