Noise

[claymore]

Every single thing we do creates noise no matter how small or loud, but what is the scientific explanation for the noise created when two objects come together, like dropping a spoon on the floor ,hammering a nail, slamming a door etc.I know sound waves carry the sound to our ears but that does n`t explain the cause of that noise.

[ChuckFickens]

Sound waves a vibrations, they are caused by the item "making" the noise vibrating.

[ZedBloke]

annoyingus racketus?

[Khandro]

Noise is energy.

[Teddio]

Sound waves are compressions and rarefactions in the air. When you drop a spoon and it hits the floor it will vibrate against the air, propagating the "squashy" regions and "stretchy" regions which is the sound wave.

[vascop]

When you pluck a guitar string it vibrates and causes compressions/decompressions in the air which travel to your ear.
Same thing happens when you slam a door etc. The impact of the two objects causes them to distort slightly and then they vibrate back and to for a short time and compress and decompress the air which again travel to your ear.
Because these objects (like doors and door frames) are very rigid compared to a guitar string, they soon stop vibrating and so the sound only lasts for a short time.
Think also of a ball hitting a tennis racquet: the ball is compressed slightly and the racquet strings are stretched slightly. When the ball springs back and the strings tighten up again they create sound waves. Again the ball is difficult to compress and the strings are hard to stretch and so they soon return to where they were and so the sound doesn't last for long.

[jomifl]

One of the factors which determines how long a noise lasts or it's 'sustain' (as well as the mechanical properties of the object) is the rate at which the energy of vibration is converted into sound. That is why cheap electric guitar note lasts longer than good quality acoustic guitar note. All the sound made by an acoustic guitar come from the energy put into plucking the string, whereas an electric guitar uses an external energy source to make the sound and uses very little energy from the strings.

[pdq1]

Technology currently exists to remove noise. For instance some flights issue passengers with BOSE headphones that cancel ambient noise. The technology is fairly simple. Each noise creates a sound wave of varying frequencies and amplitude. The technology is to create an anti-wave and add it to the original noise and that cancels out the sound wave.

Another application of anti-sound waves is a road transformer in Cambridge that can annoy residents with an annoying hum but is cancelled out with this technology.

[Cruciformist]

Change of energy form from kinetic to sound. There is also heat energy produced in every collision, but in the case of your dropped spoon it would be represented by a miniscule rise in temperature of bboth the spoon and the floor.

[jack_lfc]

sound is just the vibration of practicals and then two things come into contact the practicals vibrate due the the transfer of kinetic energy, this causes a vibration we call sound

[vascop]

Presumably you mean particles not practicals. Is that correct