7/26/2019 Scientific reasons.docx

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Scientifc reasons

Q= Why cup our hands before shouting?

The science behind sound

It has something to do with sound waves and the way we hear. The vibrations of vocal chords in the

throat produce sound waves, which come out through our mouth and travel through the air in all

directions. The vocal chords are tiny strings, which hang from our voice box or larynx. The sound,

which we produce, spreads out in all directions like ripples in a pond.

When these waves strike a person's ear, she or he is able to hear our sound. When the waves spread out

in all directions, a person standing at a distance is not able to hear it with intensity, for the energy of

the sound waves is also spread out.

But, when we cup our hands around our mouth, the sound waves travel only in one direction. The

intensity of the sound waves does not decrease. Thus, the sound can travel much further and clearly

reach a person standing at a distance. upping your hands around your mouth is a simple method of

making your voice reach farther.

Why do we lean orward while climbing a hill ?

We keep our body balanced on 2 feet by keeping Centre o Gravity

( COG ) of our body between 2 feet. It acts normal to the sea level vertically

downwards.

While walking on normal surface also , we keep this COG between our feet .

If COG goes out , we fall as we lose balance.

While climbing up , we have to bend forward to keep this COG intact. If we do

not bend forward , the feet position will get ahead of COG and we will fallbehind. o ,to keep the COG between feet , we must bend forward.