Light waves have some similarities with water and sound waves, but they are not exactly the same. describe all the differences you can think of between light waves, sound waves, or water waves. i need at least 7 or the answer will be considered incomplete

Nevertheless, they have some differences:

1. Light waves are electromagnetic waves, while sound and water waves are mechanical waves, this is the first and principal difference.  

2. Electromagnetic waves can propagate in vacuum (they do not need a medium or material), but mechanical waves obligatory need a material to propagate

3. Light waves are always transversal waves, this means the oscillatory movement is in a direction that is perpendicular to the propagation; but mechanical waves may be both: longitudinal waves (the oscillation occurs in the same direction as the propagation) or transversal waves.

4. Electromagnetic waves propagates at a constant velocity (Light velocity) while the velocity of mechanical waves will depend on the type of wave and the density of the medium or material.

5. Mechanical waves are characterized by the regular variation of a single magnitude, while electromagnetic waves are characterized by the variation of two magnitudes: the electric field and the magnetic field

6. Water waves are 2-dimensional waves, while the light and the sound are tridimensional spherical waves

7. Light waves transports energy in the form of radiation, while mechanical waves transport energy with material

conservation of mass

mass before something happens = mass afterwards