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प्रश्न
What is so special about the combination e/m? Why do we not simply talk of e and m separately?
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उत्तर
The basic relations for electric field and magnetic field are `("eV" = 1/2 "mv"^2)` and `("eBv" = ("mv"^2)/"r")` respectively
These relations include e (electric charge), v (velocity), m (mass), V (potential), r(radius), and B (magnetic field). These relations give the value of velocity of an electron as `["v" = sqrt(2"V"("e"/"m"))]` and `["v" = "Br"("e"/"m")]` respectively.
It can be observed from these relations that the dynamics of an electron are determined not by e and m separately, but by the ratio e/m.
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संबंधित प्रश्न
The threshold frequency for a certain metal is 3.3 × 1014 Hz. If light of frequency 8.2 × 1014 Hz is incident on the metal, predict the cut-off voltage for the photoelectric emission.
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(b) Is the formula you employ in (a) valid for calculating the radius of the path of a 20 MeV electron beam? If not, in what way is it modified?
Is the formula you employ in (a) valid for calculating radius of the path of a 20 MeV electron beam? If not, in what way is it modified?
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| Metal | Work Function (eV) |
| Na | 1.92 |
| K | 2.15 |
| Ca | 3.20 |
| Mo | 4.17 |
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