Chapter 20, Problem 47A

Why is it that when cars pass each other at high speeds on the road, they tend to be drawn to each other?

To determine

To explain: The reason for the cars such that they tend to draw each other when car passes each other at high speed on the road.

Explanation of Solution

Introduction:

The fluid dynamics plays a crucial role when body moves through the fluid. When air passed through the narrow region, due rapid change in pressure of air; its velocity increases. Increase in velocity results into the large kinetic energy.

When car with high velocity moves on the road, it exert the force on air just outside it. It is when two cars pass one another, due to high velocity, narrow region forms between them. In narrow region pressure drops down. Decrease in the pressure between two cars, results into pressure difference. Therefore, when cars move each other pressure exert from the outside region and hence they tend to draw each other. The schematic representation of the situation can be shown below.

Conclusion:

Therefore, when car moves with high velocity, the narrow region between them creates a very low-pressure region. Pressure difference creates between outside region and narrow region between cars. Due to large pressure difference, cars move from outside to the narrow region.