b) Stationary vs progressive waves

c) similarities and the differences between stationary and progressive waves

energy transfer

• progressive wave

  • net energy transfer → in the direction of wave motion

• stationary wave

  • no net energy transfer → progressive waves travel in opposite directions

amplitude

• progressive wave

  • constant amplitude

• stationary wave

  • fluctuating amplitude

    • zero amplitude at nodes

    • maximum amplitude at antinodes

phase difference for stationary waves

• if two points are separated by zero or an even number of nodes

  • they reach their maximum and minimum displacements at the same time → they are in phase

• if two points are separated by an odd number of nodes

  • one reaches its maximum displacement as the other reaches its minimum displacement → they are in antiphase