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Light of wavelength 330nm falling on a p...

Light of wavelength `330nm` falling on a piece of metal ejects electrons with sufficient energy with required voltage `V_0` to prevent them reaching a collector. In the same set up, light of wavelength `220 nm` ejects electrons which require twice the voltage `V_0` to stop them in reaching a collector. the numerical value of voltage `V_0` is

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The correct Answer is:
`15//8 V`
`E_(330)=12400/3300=3.7575 eV`
`E_(220)=12400/2200=5.636 eV`
Let work function be `phi`
`eV_(0)=(3.7575-phi)e, 2eV_(0) (5.6363-phi)e`
`V_(0)=1.87 V`
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ALLEN -SIMPLE HARMONIC MOTION-Exercise - 04[A]
  1. When a monochromatic point source of light is at a distance of 0.2 m...

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  2. Light of wavelength 330nm falling on a piece of metal ejects electrons...

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  3. The graph between 1/lambda and stopping potential V(0) of two metals h...

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  4. The surface of cesium is illuminated with monochromatic light of vario...

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  5. A metallic surface is illuminated alternatively with light of waveleng...

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  6. What is the effect on the maximum kinetic energy and the number of pho...

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  7. A small 10 W source of wavelength 99 nm is held at a distance 0.1 m fr...

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  8. An electron of mass m and charge e initially at rest gets accelerated ...

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  9. Assume that the de-Brogile wave associated with an electron can form a...

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  10. An electron, in a hydrogen like atom , is in excited state. It has a t...

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  11. An electron in the ground state of hydrogen atom is revolving in antic...

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  12. The follwing diagram indicates the energy levels of a certain atom whe...

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  13. A hydrogen like atom (atomic number Z) is in a higher excited state o...

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  14. Find the ratio of series limit wavelength of Balmer series to waveleng...

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  15. An electron joins a helium nucleus to form He^(+). Find the wavelength...

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  16. An X-ray tube, operated at a potential difference of 40 kV, produce he...

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  17. The Ka X-ray of molybdenum has wavelength 71 pm. If the energy of a mo...

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  18. The positron is a fundamental particle with the same mass as that of t...

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  19. The binding energies per nucleon for deuteron (.1H^2) and helium (.2He...

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  20. If there times of lambda(min) of continuous X-ray spectrum of target m...

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