Question

Question 5 Calculate the wavelength of the following subjects using de Broglie equation. (1) A baseball of 145 g and moving at a speed of 45 m/s (about 100 miles per hour) (2) An electron moving at a speed of 1.2 x 107 m/s (3) Which one of the above is likely to behave like a wave, such as interference and diffraction?

Answer 1

de broglie equation is

wavelength ($\lambda$ ) = (h/mv)

1)

m =145 g = 0.145 Kg

v = 45 m/s

$\lambda$ = (6.626×10^-34/0.145×45)

or, $\lambda$ =1.01×10^-34 m.

2)

for electron

m =9.1×10^-31 Kg

v =1.2×10⁷ m/s

so, wavelength ($\lambda$ ) =(6.626×10^-34/9.1×10^-31×1.2×10⁷)

or, wavelength ($\lambda$) = 6.06×10^-11 m .

3)

Wavelength of baseball is negligible.

but wavelength of electron is considerable ( within the range of atomic dimension) hence electron will behave like wave.