drum

Examples of drum in the following topics:

• Standing Waves in Other Objects

  • Membranophones are instruments in which the sound is produced by making a membrane vibrate; drums are the most familiar example.
  • Most drums do not produce tones; they produce rhythmic "noise" (bursts of irregular waves).
  • Some drums do have pitch, due to complex-patterned standing waves on the membrane that are reinforced in the space inside the drum.
  • Can you hear the difference that size makes, as opposed to differences in timbre produced by different types of drums?
  • Like most drums, they don't have a particular pitch, but make more of a "noise"-type sound.

• Photocopy Machines and Printers

  • In the first step of xerography, a high-voltage device (either a corona wire or charge roller) charges a cylindrical drum.
  • The areas of the drum exposed to light then discharge to the ground; the other parts of the drum (which are not conductive, having not been exposed to light) remain negatively charged.
  • Thus, the result is an electric image on the surface of the drum.
  • When it is placed on the drum, it is attracted to the negative (black) areas.
  • The image with toner on the drum is transferred to a piece of paper with more negative charge than the drum.

• Audition: Hearing, the Ear, and Sound Localization

  • It includes the pinna, the ear canal, and the most superficial layer of the ear drum, the tympanic membrane.
  • The sound waves enter the ear canal, which amplifies the sound into the ear drum.
  • The middle ear is an air-filled tympanic (drum-like) cavity that transmits acoustic energy from the ear canal to the cochlea in the inner ear.
  • The malleus (Latin for "hammer") is connected to the mobile portion of the ear drum.
  • The vibrations of the ear drum cause oscillations in the three bones in the middle ear, the last of which sets the fluid in the cochlea in motion.

• Degeneracy

  • The same thing happens with the drum.
  • For example, in Figure 2.4 you will see plots of the modes $n=1 ~~m=2$ and $m=1 ~~n=2$ for a drum for which $L_x = L_y = 1$.
  • Suppose we excited the drum at a frequency $\omega_{12} = \omega_{21}$?
  • Therefore we have proved that if the ratio of the lengths of the sides of the drum is irrational, then there is no degeneracy.
  • Figure 2.4: Modes 21 (left) and 12 (right) for a square drum.

• Putting benefit perception and service together

  • Afterwards, Safechem cleans up the work site, transports the used solvents back to Safechem, and cleans and/or recycles everything that was used – including the solvents, the washers, the spray guns and the steel drums – in preparation for the next customer.

• 2-D separation of variables

  • Let's consider a rectangular drum (a thin membrane, clamped on the sides) of lengths $L_x$ and $L_y$.
  • So the spatial variation of the drum's vibration must be proportional to
  • Figure 2.2: The first four modes of a rectangular drum.
  • The aspect ratio of the drum is 1.5.

• Reception of Sound

  • the middle ear: transduces the mechanical pressure signals from the ear drum into electrical signals
  • They then travel through the auditory canal, causing vibration of the thin diaphragm called the tympanum, or ear drum, the innermost part of the outer ear .

• Otitis Media

  • Sometimes the ear drum ruptures, discharging pus from the ear, but the ruptured drum will usually heal rapidly.

• Student Subcultures

  • Scenes can be used to describe geographic subsets of a subculture, such as the Detroit drum and bass scene or the London goth scene.
  • The term can be used to describe geographic subsets of a subculture, like the Detroit drum and bass scene or the London goth scene.

• Suggested Listening