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Photons absorbed in matter are converted to heat. A source emitting n photons/ sec of frequency `nu` is used to convert 1kg of ice at `0^(@)C` to water at `0^(@)C`. Then, the time T taken for the conversionA. decreases with increasing n, with v fixedB. decreases with n fixed, v increasingC. remains constant with n and b changing such that nv= constantD. increases when the product nv increases |
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Answer» Energy spent to convert ice into water `" "` = mass x laten heat `" "=mL=(1000g)xx(80cal//g)` `" "` = 80000 cal Energy of photons used `=nTxxE=nTxxhv` `So, " "nThv=mLimpliesT=(mL)/(nhv)" "[becauseE=hv]` `therefore " "Tprop1/n,` when n is fixed. `therefore " "Tprop1/v,` when n is fixed. `impliesTprop1/(nv)` Thus, T is constant, if nv is constant. |
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