Afree electron with initial energy of 9 ev encounters a rectangular potential step of energy 12 ev and width of 0.4 nm. what is the probability that the electron will tunnel the barrier ?

The  probability that the electron will tunnel the barrier is 0.25%.

Explanation:

Given that,

Initial energy = 9 eV

Potential energy = 12 eV

Width = 0.4 nm

Using formula of transmission coefficient

.....(I)

We need to calculate the value of k

Where, m = mass of electron

E = initial energy

v=potential energy

Put the value into the formula

We need to calculate the probability that the electron will tunnel the barrier

Using the formula of tunnel barrier

Where,

Put the value into the formula

Hence, The  probability that the electron will tunnel the barrier is 0.25%.

f=ma newton

f=100x2.5=250n

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