The change in momentum is 240 kgm/s
<u>Explanation:</u>
Given:
Force, F = 120N
Time, dt = 2 sec
Change in momentum, dP = ?
We know,

On substituting the value we get:

Therefore, change in momentum is 240 kgm/s
Answer:
c. 0.12 m/s
Explanation:
by using momentum formula 
we get

More energy is used in creating a louder sound from the mouth.
<h3>What must you do to produce a louder sound?</h3>
We use more energy in order to produce a louder sound because energy is the thing that helps in the formation of loud sound. Loudness is dependent on the energy that creates loud sound in the mouth. More energy we apply, more loud sound will produce. Energy is the main factor which gives us a loud sound in each and every instruments. Without, we can't imagine loud sound.
So we can conclude that more energy is used in creating a louder sound from the mouth.
Learn more about sound here: brainly.com/question/1199084
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