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In astronomical observations, signals observed from the distant stars are generally weak. If the photon detector receives a total of `3.15xx10^(-18)J` from the radiations of `600 nm`, calculate the number of photons received by the detector. |
Answer» Where,`lambda =` wavelength of radiation h = Planck’s constant c = velocity of radiation Substituting the values in the given expression of E: `E = ((6.626 xx 10^(-34) Js)(3 xx 10^(8) ms^(-1)))/((600 xx 10^(-9) m))` `E = 3.313 xx 10^(-19) J` Energy of one photon `= 3.313 xx 10^(-19) J` Number of photons received with `3.15 × 10^(-18) J` energy `= (3.15 xx 10^(-18)J)/(3.313 xx 10^(-19) J)` `= 9.5` `~~ 10` |
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