Which of the following mechanical waves has the most energy
a
b
c
d

Explanation:

Mechanical wave are the waves that requires a medium for its propagation. The energy of wave is given by the following formula as :

Where

h = Planck's constant

c = speed of light

= wavelength

So, the energy of wave is inversely proportional to its wavelength.

From the given figure, the distance between two consecutive crests and trough is minimum in figure (4). So, figure (4) has most energy.