Science - Waves

• What are the two main types of waves discussed in the video?

  Transverse and longitudinal waves
• What is the primary function of waves as described in the video?

  Waves transfer energy from one place to another without transferring matter
• How does our brain interpret the energy transferred by waves?

  Our brain builds images and tunes from the light and sounds received
• What does a displacement-distance graph represent in relation to waves?

  It shows how far the wave has traveled and how far it has oscillated from the equilibrium point
• What is the maximum displacement of a wave called?

  Amplitude
• How is wavelength defined in the context of waves?

  Wavelength is the distance of one entire oscillation of the wave
• What is the opposite of the crest in a wave called?

  Trough
• What does a displacement-time graph represent?

  It shows how far the wave has oscillated over time
• What is the time period of a wave?

  The time it takes for one complete oscillation
• How can frequency be calculated from the time period?

  Frequency is the inverse of the time period
• If the time period of a wave is 0.5 seconds, what is its frequency?

  2 hertz
• If a wave has a frequency of 4 hertz, what is its time period?

  0.25 seconds
• How is wave speed calculated?

  Wave speed is calculated by multiplying wavelength by frequency
• What is the wave speed of a sound wave with a frequency of 400 hertz and a wavelength of 70 centimeters?

  280 meters per second
• What characterizes transverse waves?

  Oscillations are perpendicular to the direction of energy transfer
• What are some examples of transverse waves?

  Electromagnetic waves, ripples in water, and waves on strings
• How do longitudinal waves differ from transverse waves?

  Longitudinal waves have oscillations that are parallel to the direction of energy transfer
• What are examples of longitudinal waves?

  Sound waves and seismic p waves
• What are the key differences between transverse and longitudinal waves?

  • Transverse waves: oscillations are perpendicular to energy transfer
  • Longitudinal waves: oscillations are parallel to energy transfer
  • Examples: Transverse (light, water waves), Longitudinal (sound, seismic p waves)
• What are the two types of reflection discussed in the video?

  Specular and diffuse reflection
• What happens when a wave arrives at a boundary between two materials?

  It can be absorbed, transmitted, or reflected.
• What is the focus of the video?

  The focus is on how waves are reflected off a boundary.
• What is the first option that can happen when a wave hits a boundary?

  The wave might be absorbed by the material.
• What does it mean for a wave to be transmitted?

  It means the wave enters the material and continues traveling through it.
• What is the rule regarding the angles of incidence and reflection?

  The angle of incidence is always equal to the angle of reflection.
• How do you start drawing a ray diagram for reflection?

  You start at the boundary between the two materials.
• What is the normal in a ray diagram?

  The normal is a dashed line that is perpendicular to the surface.
• If the angle of incidence is 45 degrees, what is the angle of reflection?

  45 degrees
• What is the point where the incoming ray touches the boundary called?

  The point of incidence
• What characterizes specular reflection?

  It occurs on smooth surfaces where all normals are in the same direction.
• What happens to light rays when they reflect off a rough surface?

  They are reflected in different directions due to varying normals.
• Why can't you see your reflection in a piece of paper?

  Because it has a rough surface that scatters light.
• What is the relationship between the angle of incidence and the angle of reflection in both specular and diffuse reflection?

  In both types, the angle of incidence is always equal to the angle of reflection.
• What happens to the normals on a rough surface?

  They point in different directions due to the surface's bumps.
• What is the main takeaway from the video regarding reflection?

  Reflection occurs when the angle of incidence equals the angle of reflection.
• What are the three possible outcomes when a wave hits a boundary?

  • Absorption: Energy is transferred to the material.
  • Transmission: Wave enters and continues traveling.
  • Reflection: Wave bounces off the surface.
• What are the differences between specular and diffuse reflection?

  Specular Reflection:

  • Occurs on smooth surfaces
  • Produces clear images

  
  

  Diffuse Reflection:

  • Occurs on rough surfaces
  • Scatters light in multiple directions
• What is the phenomenon called when light waves change direction as they pass from one medium to another?

  Refraction
• Why do waves travel at different speeds in different materials?

  Because different materials have different densities
• How does the density of a material affect the speed of electromagnetic waves like light?

  The higher the density of the material, the slower the wave will travel through it