Chapter 26, Problem 7A

(a)

To determine

The speed of dry air at room temperature.

Answer to Problem 7A

The speed of sound in dry air at room temperature is $340m/s$ .

Explanation of Solution

Introduction: The speed of sound in depend on the temperature & mass of particle.

The speed of sound of dry air at 0° C is 330 m/s . As the temperature increase the speed of sound increase thus the speed of sound in dry air at room temperature (20°C) is $340m/s$

Conclusion: The sound speed is 340 m/s.

(b)

To determine

The effect of temperature on the speed of sound .

Answer to Problem 7A

As the temperature increases the speed of sound increases.

Explanation of Solution

Introduction: The speed of sound depend on the temperature .

As the temperature increases the molecules speed increase. This increase in the speed will transit the sound wave faster than it before . Thus, as the temperature increases the sound travel faster.

For example :

The speed of sound of dry air at 0° C is 330 m/s . As the temperature increase the speed of sound increase thus the speed of sound in dry air at room temperature (20°C) is $340m/s$

Conclusion: The speed of sound increases with increases in the temperature.