a boy blowing a whistle sends in air at 2g/s with speed of 150 m/s. his lung power is

To determine the lung power of the boy blowing the whistle, we need to consider the relationship between the mass flow rate of the air he expels and the speed at which it is expelled. Lung power can be calculated using the formula for power, which is the product of force and velocity. In this case, we can derive the force from the mass flow rate and the velocity of the air.

Understanding the Components

First, let's break down the information provided:

• Mass flow rate (ṁ): 2 grams per second (g/s), which we need to convert to kilograms per second (kg/s) for standard SI units.
• Velocity (v): 150 meters per second (m/s).

Converting Units

Since 1 gram is equal to 0.001 kilograms, we convert the mass flow rate:

2 g/s = 2 × 0.001 kg/s = 0.002 kg/s.

Calculating Power

Power (P) can be calculated using the formula:

P = ṁ × v

Substituting the values we have:

P = 0.002 kg/s × 150 m/s

P = 0.3 watts.

Interpreting the Result

The calculated lung power of 0.3 watts indicates the rate at which the boy can do work by expelling air through the whistle. This is a relatively small amount of power, which is typical for activities like blowing a whistle, where the effort is not extremely strenuous.

Real-World Context

To put this into perspective, consider that a standard light bulb uses about 10 watts of power. The boy's lung power is only a fraction of that, illustrating how everyday activities require varying amounts of energy. In sports or singing, for example, lung power can be significantly higher due to increased airflow and effort.

In summary, the boy's lung power while blowing the whistle is 0.3 watts, derived from the mass flow rate of air and its velocity. This calculation not only highlights the physics behind the action but also connects to broader concepts of energy and power in everyday life.