PAPER 2 REVISION

• What is amplitude in wave terminology?

  Maximum displacement from rest position
• How is wave speed calculated?

  Wave speed = frequency × wavelength
• What is frequency in wave terminology?

  Number of waves passing a point per second
• What is wavelength?

  Distance between two points on a wave
• What happens to wave speed and wavelength when waves travel between media?

  Wave speed and wavelength may change, frequency stays the same
• How can waves be described?

  As oscillations or vibrations about a point
• What distinguishes transverse waves from longitudinal waves?

  Transverse waves have perpendicular vibrations, longitudinal waves have parallel vibrations
• How do you create a transverse wave using a slinky?

  Move the slinky up and down
• How do you create a longitudinal wave using a slinky?

  Bump the slinky back and forth
• What travels in ripples on water and sound waves in air?

  The wave itself, not the medium
• What is the peak of a transverse wave?

  The highest point of the wave
• What is the trough of a transverse wave?

  The lowest point of the wave
• What is amplitude in a transverse wave?

  Height from equilibrium to peak or trough
• How is wavelength measured in a transverse wave?

  Distance between two identical points on the wave
• What is the law of reflection?

  Angle of incidence equals angle of reflection
• How are angles measured in reflection?

  From the normal line, not the surface
• What happens when waves meet a boundary between materials?

  They can reflect, absorb, or transmit
• What is ultrasound?

  Waves above 20 kHz frequency
• What are some uses of ultrasound?

  Imaging, cleaning, detecting cracks
• How does ultrasound imaging work?

  Ultrasound waves reflect off tissue boundaries
• How do you calculate distance using ultrasound waves?

  Distance = wave speed × time
• What is the frequency range of normal human hearing?

  20 Hz to 20 kHz
• What happens to sound waves in the ear?

  They cause vibrations in the eardrum
• How can you measure the velocity of sound in air?

  Use distance and time measurements
• How do you measure the velocity of ripples on water?

  Use a ripple tank and measure wavelength
• What is the electromagnetic spectrum?

  A continuous range of electromagnetic waves
• What mnemonic helps remember the order of electromagnetic waves?

  (R)abbits (M)eet (I)n (V)ery (U)nusual (G)ardens
• What are the properties of radio waves?

  Longest wavelength, lowest frequency, lowest energy
• What happens to electromagnetic waves as frequency increases?

  They become more dangerous
• What can microwaves cause in body cells?

  Internal heating of body cells
• What can ultraviolet waves cause?

  Skin cancer and eye damage
• What is the effect of x-rays on body cells?

  They can cause mutations and damage
• What happens when radio waves are absorbed?

  They create an alternating current
• What occurs when electromagnetic waves change velocity?

  They are refracted and change direction
• How are angles measured in refraction?

  From the normal line, not the surface
• What are wavefronts?

  Imaginary lines perpendicular to wave direction
• What do convex lenses do to light?

  They converge light rays
• What types of images can convex lenses produce?

  Real, virtual, magnified, or diminished
• What is the focal length?

  Distance from lens to principal focus
• What types of images do concave lenses form?

  Upright, diminished, and virtual images