A:For microscope particles or sub microscopic particles wavelength of de-Broglie is important.
R:If velocity is constant then de-Broglie wavelength is inversely proportional to mass of particle.

Options

A. Both assertion and reason are true and the reason is correct explanation of the assertion.
B. Both assertion and reason are true but reason is not correct explanation of the assertion
C. Assertion is true but the reason is false
D. Both assertion and reason are false.

Answer

A

Explanation

Both assertion and reason are true and the reason is correct explanation of the assertion
de-Broglie wavelength,
I `lambda=(h)/(p)=(h)/(mv)`,if v is constant then ,
`lambda prop(1)/(m)[becauseh="constant"]`