Question

The mass of electron is 9.1 into 10 to the power minus 31 kilograms and its kinetic energy is 3 into 10 to the power minus 25 joules calculate its wavelength

Answer 1

Answer: 8.967 × 10^-7 m

Explanation: From the de-Broglie Equation:

Wavelength= Planck's Constant/Momentum

and Momentum=√(2 × Kinetic Energy × mass)

On substituting values, one gets the result.

Answer 2

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.