western region ext1maths trials?? (1 Viewer)

Dumsum

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We may have done Western Region, not sure, probably a mixture of a few sources. Was there a question on the area of the shadow of this fence thing? And the rate at which it changes as the sun goes down?
 

crazy_viet

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yup thats it, i got that =) thevery last question, grr. i drew the graph, but from 0 to 2pi! so ripped it up redid it in the last few secs, but didnt explain what was goin on with the shadow!
 

crazy_viet

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as i recall, the height was 20, length 30 [metres]
finding area was 300/tanA where A was the angle between top of fence to top of shadow to base of fence.

so tanA = 20/length of shadow

therefore length of shadow is 20/tanA

area of shadow is (base x height)/2

= (30x20/tanA)/2
= 600/2tanA
= 300/tanA

thats the first bit..
 

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