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Anit [1.1K]
2 years ago
14

‏Explain how an electron emitted by the photoelectric effect can have kinetic energy less than threshold energy ?

Physics
1 answer:
xenn [34]2 years ago
4 0

Answer:

the photons (quanta of light) collide with the electrons, these electrons have to overcome the threshold energy that is the energy of union with the metal, and the energy that remains is converted to kinetic energy.

          K = E - Ф

Explanation:

The photoelectric effect is the emission of electrons from the surface of a metal.

This was correctly explained by Einstein, in his explanation the energy of the photons (quanta of light) collide with the electrons, these electrons have to overcome the threshold energy that is the energy of union with the metal, and the energy that remains is converted to kinetic energy.

          E = hf

          E = K + Ф

          K = E - Ф

The energy of the photons is given by the Planck relation E = hf and according to Einstein the number of joints must be added

            E = n hf

Therefore, depending on the value of this energy, the emitted electrons can have energy from zero onwards.

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MrRa [10]

Answer:

D. The moon is closer to Earth than the sun.

Explanation:

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Since gravity variate with the distance:

   

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8 0
3 years ago
What is the half life of Strontium-90? Explain your answer
nadezda [96]
Hey there, 

Question: "<span>What is the half life of Strontium-90? Explain your answer"

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Answer:

Kinetic energy is maximum when the player hits the ball.

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