(b) A wind-tunnel experiment is performed on a small 1:5 linear-scale model of a car, in order to assess the drag force F on a new full-size car design. A dimensionless "drag coefficient" Ca is defined by C,= where A is the maximum cross-scctional area of the car in the flow. With the model car, a force of 3 N was recorded at a flow velocity u of 6 ms. Assuming that flow conditions are comparable (i.e., at the same Reynolds number), calculate the expected drag force for the full-sized car when the flow velocity past it is 31 m s (equivalent to 70 miles per hour). [The density of air p= 1.2 kg m.]

(b) A wind-tunnel experiment is performed on a small 1:5 linear-scale model of a car, in order to assess the drag force F on a new full-size car design. A dimensionless "drag coefficient" Ca is defined by C,= where A is the maximum cross-scctional area of the car in the flow. With the model car, a force of 3 N was recorded at a flow velocity u of 6 ms. Assuming that flow conditions are comparable (i.e., at the same Reynolds number), calculate the expected drag force for the full-sized car when the flow velocity past it is 31 m s (equivalent to 70 miles per hour). [The density of air p= 1.2 kg m.]

Elements Of Electromagnetics

7th Edition

ISBN:9780190698614

Author:Sadiku, Matthew N. O.

Publisher:Sadiku, Matthew N. O.

ChapterMA: Math Assessment

Section: Chapter Questions

Problem 1.1MA

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Question

(b) A wind-tunnel experiment is performed on a small 1:5 linear-scale model of a car, in order
to assess the drag force F on a new full-size car design. A dimensionless "drag coefficient"
Ca is defined by
C, =-
pu'A
where A is the maximum cross-sectional area of the car in the flow. With the model car, a
force of 3 N was recorded at a flow velocity u of 6 m s. Assuming that flow conditions
are comparable (i.e., at the same Reynolds number), calculate the expected drag force for
the full-sized car when the flow velocity past it is 31 m s (equivalent to 70 miles per
hour). [The density of air p= 1.2 kg m.]

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