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In the Davisson and Germer experiment, the velocity of electrons emitted from the electron gun can be increased by:

1. increasing the potential difference between the anode and filament
2. increasing the filament current
3. decreasing the filament current
4. decreasing the potential difference between the anode and filament

Correct answer: increasing the potential difference between the anode and filament

Solution

The velocity of electrons in the Davisson and Germer experiment is directly related to their kinetic energy, which increases with the potential difference between the anode and filament. Increasing this potential difference accelerates the electrons to higher velocities.

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