Concept-Development Practice Page 26-1

Concept-Development Practice Page 26-1

Sound:

1) Two major classes of waves are longitudinal and transverse. Sound waves are:

Answer: Longitudinal

2) The frequency of a sound signal refers to how frequently the vibrations occur. A high-frequency sound is heard at a high:

Answer: Pitch

3) The sketch questions answer would be: 2.5

4) Compared to the wavelengths of high-pitched sounds, the wavelengths of low-pitched sounds are:

Answer: Long

5) Suppose you set your watch by the sound of the noon whistle from a factory 3 km away:

a. Compared to the correct time, your watch will be:

Answer: behind

b. It will differ from the correct time by:

Answer: 9 seconds

6) Sound waves travel fastest in:

Answer: solids

7) If the child’s natural frequency of swinging is once each 4 seconds, for maximum amplitude the man should push at a rate of once each:

Answer: 4 seconds

8) If the man is Question 7 pushes in the same direction twice as often, his pushes:

Answer: will not

Be effective because

Every other push will oppose the motion of the swing

9) The frequency of the tuning fort is 440 hertz. It will NOT be forced into vibration by a sound of:

Answer: 220 hertz

10) Beats are the result of the alternate cancellation and reinforcement of two sound waves of:

Answer: slightly different frequencies

11) Two notes with frequencies of 66 and 70 Hz are wounded together. The resulting beat frequency is:

Answer: 4 hertz

12) The accepted value for the speed of sound in air is 332m/s at 0⁰C. The speed of sound in air increases 0.6m/s for each Celsius degree above zero. Compute the speed of sound at temperature of room you are now in:

Answer: 332m/s+ (0.6) (20⁰C)

=344m/s @20⁰C