Consider a beam of free particles that have a certain non-relativistic
kinetic energy K. If we double K, what happen to the beam's deBroglie
wavelength?

A. it increases by a factor of 2.

B. it increases by a factor of the square root of 2.

C. it remains the same

D. it decreases by a factor of 2.

E. it decreases by a factor of the square root of 2.