Answer:
1. The sound becomes louder by increasing its amplitude
2. The pitch of sound increases by increasing its frequency.
Explanation:
Q1.
The characteristic of sound, which is related to the amplitude of sound wave is <u>Loudness</u>. The amplitude of a wave is associated to the energy carried by it. Therefore, when the amplitude of sound is increased, it increases its energy and thus, we hear a louder sound.
Q2.
The characteristic of sound associated with the frequency of wave is the <u>Pitch</u>. When the frequency of sound wave is increased, its wavelength decrease and the sound is heard at a faster speed. This causes the pitch of sound to get high. And as a result we listen a shrill sound. Therefore, by increasing the frequency of sound, the pitch of sound is increased and a shrill sound is heard.