Question

a wave that is formed when waves of equal amplitude and wavelength traveling in opposite directions continually interfere with each other is

reflection.
a standing wave.
the doppler effect.
diffraction.

question #8
the pencil appears broken in the picture above because of

interference.
diffraction.

Explanation:

1. For the first question, a standing - wave is formed when waves of equal amplitude and wavelength traveling in opposite directions continuously interfere with each other. Reflection is the bouncing back of a wave from a surface, the Doppler effect is related to the change in frequency due to relative motion, and diffraction is the bending of waves around obstacles.
2. For the second question, the pencil appears broken in water because of refraction. Refraction is the bending of light as it passes from one medium (air) to another (water). Interference is the superposition of two or more waves, and diffraction is the bending of waves around obstacles. Since refraction is not an option, we assume the closest concept among the given ones is related to the bending of light which is not accurately represented by interference or diffraction in this context.

Answer:

1. A standing wave.
2. No correct option among the given ones (but should be refraction).