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```
A certain dye absorbs 4530 A and fluoresces at 5080 A these being wavelengths of max. absorption that under conditions 47% of the absorbed energy is emitted. Calculate ratio of quanta emitted to the number absorbed.

```
11 years ago

```							let no. of femitted quanta = n1
& of absorbed = n2
frequency of emitted quanta  f1 =  c/ 5080* 10^-10
energy e1  =  h*f1 = h*  c/ 5080* 10^-10
frequency of absorbed quanta f2 = c/ 4530* 10^-10
energy e2 =   h*  c/ 4530* 10^-10
total energy of emitted quanta =  0.47 0f  absorbed quanta
hence,
n1* h*  c/ 5080* 10^-10 =   0.47*n2* h*  c/ 4530* 10^-10
n1/5080 = 0.47 * n2 /4530
n1/n2 =  0.527
```
11 years ago
```							Quantum efficiency(Q.E) is defined as ratio of quanta emitted to the number absorbed
it is expressed in ratio of energies
quanta absorbed on dye : E = hc/lamda = 1242 eV-nm /453 nm = 2.742 eV
quanta exhibited/undergo fluorescence on dye : E = hc/lamda = 1242 eV-nm /508 nm = 2.445 eV

Q.E = 0.47*2.742 / 2.445
= 0.527
or 52.7 % efficient
I'm not sure if the method was correct, plz verify with someone else
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```
11 years ago
```							E(absorbed)=1242/453=2.742 E(energy of photon)=1242/508=2.44547% of absorbed energy is re-emitted out:47/100*2.742no. of photons emitted=energy beingemitted/energy of 1 photon=47/100*2.742/2.444=0.527
```
one year ago Yash Chourasiya
246 Points
```							Hello StudentEnergy of light absorbed in an photon= hc/λabsorbed​Letn1​photons are absorbedTotal energy absorbed= n1​hc/λabsorbed​Now E of light re-emitted out in one photon= hc/λemitted​Letn2​photons are re-emitted thenTotal energy re-emitted out= n2​hc/λemitted​Eabsorbed​×47/100 = Ere−emittedout​hc/λabsorbed​× n1 ​× 47/100 = n2 × hc/λemitted​n2​/n1​ = 47/100 × λemitted​ /λabsorbed​    = (47/100) × (5080/4530)n2​/n1​ = 0.527I hope this solution will help you.
```
5 months ago
```							A certain dye absorbs 4530A∘ and fluoresence at 5080A∘ these being wavelength of maximum absorption that under given condition 47% of the absorbed energy is emitted. Calculate the ratio of the no of quanta emitted to the number absorbed.
```
4 months ago
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