What is the de-Broglie wavelength associated with an electron accelerated through a voltage of 900 V?
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2.
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4.
What is the de-Broglie wavelength of a neutron in thermal equilibrium with heavy water at a temperature T (Kelvin) and mass m?
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2.
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4.
If an electron of mass m with a de-Broglie wavelength of \(\lambda\) falls on the target in an X-ray tube, the cut-off wavelength ( λ0) of the emitted X-ray will be:
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An electron of mass m and a photon have the same energy E. Find the ratio of de-Broglie wavelength associated with the electron to that associated with the photon. (c is the velocity of light)
Which of the following figures represents the variation of the particle momentum and the associated de-Broglie wavelength?
1. | 2. | ||
3. | 4. |
Light with a wavelength of 500 nm is incident on a metal with a work function of 2.28 eV. The de Broglie wavelength of the emitted electron will be:
1. \( <2.8 \times 10^{-10} \mathrm{~m} \)
2. \( <2.8 \times 10^{-9} \mathrm{~m} \)
3. \( \geq 2.8 \times 10^{-9} \mathrm{~m} \)
4. \( <2.8 \times 10^{-12} \mathrm{~m}\)
What will be the percentage change in the de-Broglie wavelength of the particle if the kinetic energy of the particle is increased to 16 times its previous value?
1. 25
2. 75
3. 60
4. 50
The wavelength \(\lambda_{e}\) of an electron and \(\lambda_{p}\) of a photon of the same energy E are related as:
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An \(\alpha -\) particle moves in a circular path of radius 0.83 cm in the presence of a magnetic field of \(0.25 \mathrm{~Wb} / \mathrm{m}^2\). The de-Broglie wavelength associated with the particle will be:
1. | \(1~\mathring {\text{A}}\) | 2. | \(0.1~\mathring {\text{A}}\) |
3. | \(10~\mathring {\text{A}}\) | 4. | \(0.01~\mathring {\text{A}}\) |
If the momentum of an electron is changed by p, then the de-Broglie wavelength associated with it changes by 0.5%. What is the initial momentum of the electron?
1. 200p
2. 400p
3.
4. 100p