Consider a beam of free particles with a certain speed v. If we double the speed, what happens to the 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.