Question #8fa9a
1 Answer
Explanation:
First thing first, you need to know the mass of the electron in order to be able to calculate its wavelength.
The mass of the electron is listed as
#m_"electron" = 9.10938356 * 10^(-31)"kg"#
Now, the wavelength of a particle of mass
#color(blue)(lamda = h/(m * v))" "# , where
SIDE NOTE You'll often see this equation written like this
#lamda = h/p#
Here
So, plug in your values and solve for
#lamda = (6.626 * 10^(-34)color(red)(cancel(color(black)("kg"))) "m"^color(red)(cancel(color(black)(2))) color(red)(cancel(color(black)("s"^(-1)))))/(9.10938356 * 10^(-31)color(red)(cancel(color(black)("kg"))) * 2.22 * 10^(6)color(red)(cancel(color(black)("m"))) color(red)(cancel(color(black)("s"^(-1)))))#
#lamda = 3.2765 * 10^(-10)"m"#
Rounded to three sig figs, the number of sig figs you have for the speed of the electron, the answer will be
#lamda = color(green)(3.28 * 10^(-10)"m")#