An electron with KE 6 e V is incident on a hydrogen atom in its ground state. The collision.

Options

A. must be elastic
B. may be partially elastic
C. must be completely inelastic
D. may be parially inelastic.

Answer

To solve the problem of an electron with a kinetic energy of 6 eV colliding with a hydrogen atom in its ground state, we can follow these steps:

### Step 1: Understand the Energy Levels of Hydrogen
The ground state energy of a hydrogen atom is given as -13.6 eV. This means that in order to remove the electron from the hydrogen atom (ionization), an energy of 13.6 eV is required.

### Step 2: Analyze the Kinetic Energy of the Incident Electron
The kinetic energy (KE) of the incident electron is given as 6 eV. This is the energy that the electron possesses before the collision.

### Step 3: Compare the Kinetic Energy with the Ionization Energy
We need to compare the kinetic energy of the incident electron (6 eV) with the ionization energy of the hydrogen atom (13.6 eV).

- Since 6 eV < 13.6 eV, the kinetic energy of the electron is not sufficient to ionize the hydrogen atom.

### Step 4: Determine the Type of Collision
Since the kinetic energy of the electron is less than the ionization energy of the hydrogen atom, the collision cannot result in ionization.

- In this case, the collision will be elastic. In an elastic collision, the total kinetic energy is conserved, and the hydrogen atom will not lose its electron.

### Conclusion
The collision between the incident electron and the hydrogen atom in its ground state will be an elastic collision.

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