Two wave pulses travel towards each other along a string. What is the principle used to determine the resultant displacement when the pulses meet?

• A

  Diffraction — the bending of waves around obstacles.

• B

  Refraction — the change in direction of waves when passing from one medium to another.

• C

  Interference — the phenomenon where waves combine to form a resultant wave of greater or lower amplitude.

• D

  Superposition — the principle stating that the resultant displacement is the algebraic sum of the individual displacements of the waves.