Sound

• When an object travels faster than the speed of sound then they create a vibration called sonic boom! 


  Sound waves with frequency below the audible range are termed" infrasonic" and those above the audile range are termed :ultrasonic"

  Ultrasound has many medical and industrial applications.
• The SONAR full form is Sound Navigation and Ranging. SONAR has 2 parts a trasmeitter and a Reciver. The Transmitter transmittes sound wave .
• Reciver recives
• The SONAR technique is used to determine the depth of the sea and to locate under water hills. valleys, submarines, icebergs, sunken ships etc. Depth of sea= Velocity of sound in sea water x time recoded by recorder / 2.
• HUMAN EAR

  A) HUMAN EAR

  
• Echo speed formula: 2 × distance between surface and source / time
• Wave velocity formula: Velocity = Wavelength × Frequency
• Speed of sound formula: v = 331 + (0.61 ⋅ T)
• Frequency of stretched string formula: f = √T/ 2 l ( π r² d)
• Frequency of wave formula: f = 1 / t
• Energy of wave formula: E = h nu
• Wavelength is the distance between two adjacent crests or troughs of a wave. The SI unit for wavelength is meters (m)
• Velocity of wave is the distance traveled by a wave in one second. The SI unit for velocity of a wave is meters per second (m/s or ms-1)
• Amplitude is the magnitude of the maximum disturbance in the medium on either side of the mean position
• Oscillation is the change in density (or pressure) from maximum value to the minimum value and again to the maximum value
• Frequency is the number of oscillations per unit time. The SI unit for frequency is Hertz (Hz)
• Sound travels fastest in solids, slower in liquids, and slowest in gases
• Transverse Waves:

  • Particle motion is perpendicular to the direction of wave motion
  • This type of wave is a mechanical wave
  • Examples include light and Mexican wave in a stadium
• Longitudinal waves:

  • Particles travel parallel to the direction of wave motion by means of successive compressions or elongations
  • This is also a mechanical wave
  • Examples include sound waves in the air
• Pitch:

  • Higher force → higher amplitude → louder sound
• Echo:

  • The phenomenon where a sound produced is heard again due to reflection
• Applications of Ultrasound:

  • Scanning images of human organs
  • Detecting cracks in metal blocks
  • Cleaning parts that are hard to reach
  • Navigating, communicating, or detecting objects on or under the surface of the water (SONAR)
• Sonar consists of a transmitter and detector mounted on a boat or ship. The transmitter sends ultrasonic sound waves to the seabed, which get reflected back and picked up by the detector. Knowing the speed of sound in water, distance can be measured using: 2d=v×t. This method is called echolocation or echo ranging
• The ear is a sensitive organ of the human body. It is mainly involved with detecting, transmitting, and transducing sound and maintaining a sense of balance is another important function of the human ear
• The human ear includes:

  • The outer ear, or the visible part of the ear, is called the pinna
  • Pinna collects sound from the surroundings
  • Sound passes through a tube called an auditory canal
  • Eardrum (tympanic membrane) vibrates in response to incident sound waves
  • Vibrations are amplified and transmitted further by three bones hammer, anvil, and stirrup in the middle ear to the inner ear
  • In the inner ear, the cochlea converts pressure signals into electrical signals
  • Electrical signals are transmitted by the auditory nerve to the brain for interpretation