(a) If the wavelength of an electron is 4.94 ✕ 10−7 m, how fast is it moving? km/s (b) If the electron has a speed equal to 5.60 ✕ 106 m/s, what is its wavelength? m Submit Answer 10.–/10 points SerCP11 28.2.P.001. Ask Your Teacher My Notes

Respuesta :

Answer:

(a) 1.468 km/s

(b) 129.5 m

Explanation:

Use the formula for the wavelength is given by

[tex]\lambda = \frac{h}{mv}[/tex]

mass of electron, m = 9.1 x 10^-31 kg

(a) λ = 4.94 x 10^-7 m

[tex]\lambda = \frac{h}{mv}[/tex]

[tex]v = \frac{6.6\times 10^{-34}}{9.1\times 10^{-31}\times 4.94\times 10^{-7}}[/tex]

v = 1.468 x 10^3 m/s = 1.468 km/s

(b) v = 5.60 x 10^6 m/s

[tex]\lambda = \frac{h}{mv}[/tex]

[tex]\lambda  = \frac{6.6\times 10^{-34}}{9.1\times 10^{-31}\times 5.60\times 10^{6}}[/tex]

λ = 129.5 m