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Pieces of potassium (Φ = 3.68 × 10–19 J) and sodium (Φ = 4.41 × 10–19 J) metal are exposed to radiation of wavelength 290.0 nm.

What is the velocity of the electrons from sodium?

What is the velocity of the electrons from potassium?

User Boileau
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2 Answers

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Answer:The velocity of electrons from sodium and potassium can be calculated using the equation E=hf, where E is the energy of the electron, h is Planck's constant and f is the frequency of the radiation.

From the equation E=hf, f can be calculated using the wavelength of the radiation:

f = c/λ

where c is the speed of light.

Then, using E=hf and the values for E (Φ) for sodium and potassium, the velocity of the electrons can be calculated using the equation:

v = sqrt(2E/m)

where m is the mass of the electron.

Step-by-step explanation:

The velocity of electrons from sodium and potassium can be calculated using the equation E=hf, where E is the energy of the electron, h is Planck's constant and f is the frequency of the radiation.

From the equation E=hf, f can be calculated using the wavelength of the radiation:

f = c/λ

where c is the speed of light.

Then, using E=hf and the values for E (Φ) for sodium and potassium, the velocity of the electrons can be calculated using the equation:

v = sqrt(2E/m)

where m is the mass of the electron.

User Robert Tirta
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1 vote

Answer:

Step-by-step explanation:

The velocity of electrons can be calculated using the equation v = h / (mλ), where h is Planck's constant (6.63 x 10^-34 Js), m is the mass of the electron, and λ is the wavelength of the radiation.

For sodium, the electron energy is given as Φ = 4.41 × 10–19 J. To find the velocity of the electrons, we first need to convert the energy into wavelength using the equation λ = hc / Φ, where c is the speed of light (3 x 10^8 m/s).

So, for sodium:

λ = hc / Φ = 6.63 x 10^-34 x 3 x 10^8 / 4.41 x 10^-19

λ = 290 nm.

And then using the velocity equation,

v = h / (mλ) = 6.63 x 10^-34 / (9.11 x 10^-31 x (290 x 10^-9))

For potassium, the electron energy is given as Φ = 3.68 × 10–19 J, and the wavelength can be calculated in the same way as for sodium:

λ = hc / Φ = 6.63 x 10^-34 x 3 x 10^8 / 3.68 x 10^-19

λ = 290 nm.

And then using the velocity equation,

v = h / (mλ) = 6.63 x 10^-34 / (9.11 x 10^-31 x (290 x 10^-9))

Note: m is the mass of an electron, which is 9.11 x 10^-31 kg.

So, both the velocity of the electrons from sodium and potassium would be the same, given that they are both exposed to the same wavelength radiation of 290 nm.

User Suraj Nayak
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