P5.1

• What do waves transfer from one place to another?

  Energy
• In a transverse wave, how does the matter vibrate in relation to the direction of wave travel?

  Perpendicular
• What are the key components of a transverse wave?

  • Peak
  • Amplitude
  • Trough
  • Wavelength
• How is amplitude defined in a transverse wave?

  It is the height between the rest position and the peak.
• What is the definition of wavelength in a wave?

  It is the distance between one point on a wave and the same point on the next wave.
• In a longitudinal wave, how does the matter vibrate in relation to the direction of wave travel?

  Parallel
• What are the key characteristics of a longitudinal wave?

  • Compression
  • Rarefaction
  • Wavelength
• What is the definition of frequency in relation to waves?

  The number of waves passing a point every second.
• How is the period of a wave defined?

  It is the time it takes for one wave to pass (or for one complete cycle).
• What is the formula for calculating the period of a wave?

  period = $\frac{1}{frequency}$
• What is the formula for wave velocity?

  wave velocity = frequency x wavelength
• How can the speed of water waves be measured?

  By creating regular waves in a tray of water and measuring the distance between them.
• What equation is used to calculate frequency from wave velocity and wavelength?

  frequency = $\frac{wave\ velocity}{wavelength}$
• What happens to light waves when they travel from one medium to another?

  Their velocity can change, which can change their direction.
• What is refraction in the context of light waves?

  It is the bending of light when it enters a different medium.
• What happens to light when it enters a glass block?

  It slows down and bends towards the normal.
• What happens to light when it leaves a glass block?

  It speeds up and bends away from the normal.
• How does the frequency of light affect its refraction?

  The higher the frequency, the more it will refract.
• Which color of light refracts more, blue or red?

  Blue light
• What is reflection in the context of light waves?

  It is when light strikes the boundary between two media and remains in the original medium.
• What is the relationship between the angle of reflection and the angle of incidence?

  The angle of reflection is the same as the angle of incidence.
• How can the speed of sound waves be measured?

  Using an echo by recording the time taken between the sound and the echo.
• What should be done with the time recorded when measuring sound speed using an echo?

  The time is halved because it accounts for the distance there and back.
• What are the key formulae to learn regarding waves?

  1. wave velocity = frequency x wavelength
  2. period = $\frac{1}{frequency}$
• What happens to the frequency as you decrease the wavelength?

  Frequency increases as wavelength decreases.
• What equation relates wave velocity, frequency, and wavelength?

  Wave velocity = frequency x wavelength
• What happens to frequency if wavelength increases while wave velocity is constant?

  Frequency must decrease.
• What is the speed of a gamma ray with a wavelength of $5 \times 10^{-15} \text{ m}$ and frequency $6 \times 10^{22} \text{ Hz}$?


  The speed is $3 \times 10^{8} \text{ m/s}$.
• How is the speed of red light with a wavelength of $6 \times 10^{-7} \text{ m}$ and frequency $5 \times 10^{14} \text{ Hz}$ calculated?


  Velocity = $5 \times 10^{14} \text{ Hz} \times 6 \times 10^{-7} \text{ m} =$$3 \times 10^{8} \text{ m/s}$.