Waves

• Amplitude


  The displacement of the crest/trough of a wave to the equilibrium line.
• Frequency


  The number of complete waves

  per second
• Wavelength


  The distance from peak to

  peak/trough to trough on a wave
• Waves


  They transfer energy from one

  place to another without

  transferring matter
• Time period


  The time taken for one complete

  wave to pass a point.
• Equation for frequency


  Frequency=1/time period
• Equation for wave speed

  wave speed=frequency x wavelength
• Doppler effect


  Changes in

  wavelength and frequency of

  a wave based on relative

  motion of source and

  observer.
• Normal


  Reference line for which all angles are

  measured against.
• Real Image


  Image which is formed from real rays.

  It can be formed on a screen.
• Virtual image


  Image formed from virtual rays of

  light that cannot be formed on a

  screen.
• Incident ray


  The ray coming into the mirror /

  surface / material.
• Upright


  Image which is formed from real rays.

  It can be formed on a screen.
• inverted


  Upside down
• Magnified


  Image is bigger than the object
• Diminished


  Image is smaller than the object
• What are waves?

  Waves are disturbances that transfer energy from one point to another without transferring matter.
• What are the two main types of waves?

  • Transverse Waves: Oscillations are perpendicular to wave propagation (e.g., light waves, water waves).
  • Longitudinal Waves: Oscillations are parallel to wave propagation (e.g., sound waves).
• What are the characteristics of transverse waves?


  In transverse waves, the crests and troughs are clearly defined.
• What are the characteristics of longitudinal waves?

  Longitudinal waves consist of compressions and rarefactions.
• What are the key properties of waves?

  • Amplitude: Maximum displacement from rest position.
  • Wavelength (λ): Distance between two consecutive points in phase.
  • Frequency (f): Number of complete waves passing a point per second (Hz).
  • Period (T): Time taken for one complete wave to pass a point.
  • Wave Speed (v): Speed at which the wave travels through a medium.
• What is the formula for wave speed?


  $v =$$f \times \lambda$
• What does amplitude determine in a wave?


  Amplitude determines the wave's energy or intensity.
• What is the relationship between period and frequency?


  The period is the inverse of frequency: $T =$$\frac{1}{f}$.
• What happens when waves interact with materials or obstacles?

  • Reflection: Waves bounce off a surface.
  • Refraction: Waves bend when passing from one medium to another.
  • Diffraction: Waves spread out when passing through a gap or around obstacles.
  • Interference: Overlapping waves can result in constructive or destructive interference.
• What governs the reflection of light waves?


  The behavior of light during reflection follows the Law of Reflection.
• What is Snell's Law used for?


  Snell's Law governs the behavior of light during refraction.
• What is the formula for Snell's Law?


  $\frac{\sin i}{\sin r} =$$\frac{v_1}{v_2} =$$\frac{n_2}{n_1}$
• What does the refractive index indicate?


  The refractive index indicates how much light slows down when passing through a material compared to a vacuum.
• What is the formula for refractive index?


  $n =$$\frac{\text{speed of light in vacuum}}{\text{speed of light in material}}$
• What conditions are necessary for total internal reflection to occur?


  Light must travel from a denser medium to a less dense medium, and the angle of incidence must be greater than the critical angle.
• What is the critical angle?


  The critical angle is the angle of incidence in the denser medium at which the angle of refraction in the less dense medium is exactly 90°.
• What is the formula for critical angle?


  $\sin C =$$\frac{1}{n}$
• What are practical applications of total internal reflection?


  • Optical Fibers: Transmit light efficiently over long distances.
  • Endoscopes: Medical instruments that use optical fibers for internal body examination.
• What is the electromagnetic spectrum?


  • All waves are transverse and travel at the speed of light (~3 × 10⁸ m/s).
  • Includes: Radio Waves, Microwaves, Infrared, Visible Light, Ultraviolet, X-rays, Gamma Rays.
• What type of waves are sound waves?


  Sound waves are longitudinal waves.
• How does the speed of sound vary in different materials?


  The speed of sound is fastest in solids, followed by liquids, and slowest in gases.
• What are echoes?


  Echoes are reflected sound waves that can be used to measure distances.
• What is pitch related to in sound waves?

  Pitch is related to the frequency of the sound wave.
• What is loudness related to in sound waves?

  Loudness is related to the amplitude of the sound wave.