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Difficulty: MediumFluid Dynamics and Bernoulli's Principle

As a race car travels at high speeds, the air flowing through the narrow clearance between the car's flat underbody and the track surface accelerates. According to the principles of fluid dynamics, this increase in air velocity creates a region of elevated static pressure that pushes upward against the bottom of the car.

Answer: Answer

Answer

False
The statement is false. According to Bernoulli's principle, an increase in fluid velocity results in a decrease in static pressure. Therefore, the fast-moving air under the race car creates a low-pressure zone that produces downforce, rather than an upward push.

Step-by-Step Solution

1
Analyze the change in air velocity under the vehicle.
The narrow gap between the car's underbody and the track restricts the airflow area, causing the air velocity to increase in order to maintain a continuous flow.
The continuity equation dictates that fluid velocity must increase when the cross-sectional area of the flow path decreases.
2
Relate the increased velocity to static pressure using Bernoulli's principle.
According to Bernoulli's principle, the higher kinetic energy of the fast-moving air results in a simultaneous decrease in static pressure.
In a flowing fluid system, an increase in velocity is accompanied by a drop in static pressure to conserve total energy.
3
Determine the direction of the resulting force on the vehicle.
Because the static pressure under the car decreases, the relatively higher ambient pressure above the car pushes it downward, creating downforce rather than upward lift.
Objects are naturally pushed toward regions of lower pressure.

Key Concept

Bernoulli's Principle and the Continuity Equation
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Topics

Fluid Dynamics and Bernoulli's Principle

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