Question

The mass of an electron is 9.1x10-31 kg. If
its K.E. is 3.0x10-25 J, calculate its
wavelength​

Answer 1

Explanation:

The mass of an electron is 9.1 × 10–31 kg. If its K.E. is 3.0 × 10–25 J, calculate its wavelength.

Answer..

We know , KE = ½ mv2

Or

v = (2KE/M)1/2

Or

v = 811.579 m/s

Now putting the values in the de Broglie’s equation

We get

Hence, the wavelength of the electron is 8.9625 × 10–7 m.