# Engineering Math

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A Theme Park site is being designed. It will occupy a rectangular piece of land 800m by 600m. There are to be 4 particularly noisy rides. The ‘Drumbeat’ uses music which reaches a level of 95dB(A). The ‘Bigdrop’ generates screams which can reach 98dB(A). The ‘Fastride’ uses a engine which has a noise level of 101dB(A). The bend on the driving track generates noise levels up to 99dB(A).

Name the four corners of the rectangle A, B, C and D. The long sides are AB and CD, and the short sides are BC and DA.

Assume that there are noise sensitive receivers at the three following points:-

A house at point B
A first aid point at the midpoint along the side CD.
A school 20m from the midpoint of the line AB.

The noisy rides must be separated by distances of at least 60m.

You are looking for a site layout which will have the lowest noise levels at the three noise sensitive receivers. Note that it is the highest of the three noise levels which matters; you are looking for a layout which achieves the lowest value for the highest of the three noise levels. You should include with your answer any graphs you produce in your search for the lowest noise levels.

You will need to use the following equations:-
Lw= Lp+20log10(r)+8

Where Lw is the sound power level (dB(A)) at the source And Lp is the sound pressure level (dB(A))at a distance r(in metres) from the source.

The sound pressure levels must be added using the following formula:-
Ltotal=10log10(∑10^(L/10)). [Under the summasation there is a j written].

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