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The model of an aircraft is designed such that the volume of it interior airspace is 125 cm². The volume of airspace of the actual...

The model of an aircraft is designed such that the volume of it interior airspace is 125 cm². The volume of airspace of the actual aircraft is 3.375 litres.
a) Given that the wing span of the aircraft is 7.44 m, find the wingspan of the model in centimetres.
b)If the total surface area of the model is 2420 cm², find the total surface area of the actual aircraft in square metres.
c) Calculate the cost of the material used to build the actual aircraft if the material costs US $ 2.5 per square centimetre.

Answers

a) volume of actual aircraft = 3375 x 10³ cm³
Volume of model = 125 cm³
Volume scale factor v = (3375 x 10³) /125
= 27000
Linear scale factor l = 3rd root of 27000
= 30
Wingspan of model = (7.44 x 100)/30 cm
= 24.8 cm

b)Area scale factor a = l² = 900
Surface area of actual aircraft
= 2420 x 900 cm²
= (2420 x 900)/100 x 100 m
²
=217 m²

c)cost of materials = 217.8 x 10⁴ x 2.5
= 5.445 x 10⁶
= US$ 5.445 million

Githiari answered the question on April 6, 2019 at 19:29

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