Question

Which shows a decrease in fluid pressure? A. Water in a creek slows down as it enters a slow-moving river. B. Oxygen is compressed as it is put into a pressurized tank. C. A river speeds up when it moves into a narrower channel. D. A fan is turned on high speed to low speed.

Answer 1

Answer:

A

Explanation

Becasue the water level is decreasing

Answer 2

Answer:

Option D.

A fan is turned from high speed to low speed.

Explanation:

It is important to note that air is also a fluid.

In a system, static pressure of air increases with the speed of rotation of the fan. This is because when the speed of the fan is increased, the force with which it is pushing the air molecules is increased. Since pressure is a relationship between force and area, the pressure of the air molecules will be increased.

Conversely, when the speed of the fan is reduced, the priming force on the air molecules will be reduced, hence the pressure of the air will drop.

This makes option D the correct option