The diagram shows a spherical wave.

which letter represents a wavelet?

a. w
b. x
c. y
d. z

Y    

Explanation:

According to Huygen's principle, each point on a wavefront is a source of wavelets which generates the next wavefront.

In the given diagram, point source of light that is the primary source is represented by W. X and Z are wavefronts. The points marked on X are point source of wavelets. On Z, a wavelet is represented by Y. The wavelets spread out in forward direction. The envelope of wavelets forms a wavefront.

what experimental evidence led scientists to change from the previous model to this one?

a few of the positive particles aimed at a gold foil seemed to bounce back.

the colors of light emitted from heated atoms had very specific energies.

experiments with water vapor showed that elements combine in specific proportions.

cathode rays were bent in the same way whenever a magnet was brought near them.