Question

Matter waves are:

• A. electromagnetic waves
• B. mechanical waves
• C. either mechanical or electromagnetic waves
• D. neither mechanical nor electromagnetic waves

Answer 1

Answer: (D)

it is a wave associated with particles revolving in an atom around nucleus.
De broglie named these waves as matter waves or De Broglie's waves.
its wavelength is calculated from wavelength $\lambda =h/mv$,
where, $h$ is plank constant.
This theory mainly conveys the wave nature of light having energy given by plank $E=hv$.
($v$ is frequency of radiation).
These waves do not require any material medium for it propagation.
it is coming in mainly non relativistic theory.