Stationary waves are so called because in them,

Stationary waves are so called because in them,
  1. the particles of the medium are not disturbed at all
  2. the particles of the medium do not execute SHM
  3. there occurs no flow of energy along the wave
  4. the interference effect cannot be observed

Solution

In stationary waves, all particles of the medium pass through their mean position simultaneously twice in each time period. These wave do not transmit energy in the medium.

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