Calculate the rate of emission of quanta per second, when a 25watt bulb emits monochromatic yellow light of wavelength 0.57μ m .

Question

Calculate the rate of emission of quanta per second, when a 25watt bulb emits monochromatic yellow light of wavelength 0.57μ m . (A) 7.17 × 1029 s- 1 (B)  7.17 × 1011 s- 1 (C)  7.17 × 109 s- 1 (D)  7.17 × 1019 s- 1

Tardigrade Admin · Accepted Answer

(E/photon)=(h c/λ )=(6.625 × 10- 34 × 3.0 × 108/0.57 × 10- 6)=34.86 × 10- 20 J . Watt=No.ofphotons(e m i t t e d/s e c .)× (E/p h o t o n)(W a t t = 25 J s- 1) . 25=No. of photons × 34.86 × 10- 20 ∴ No. of photons emitted =(25/34.86 × 10- 20)=7.17 × 1019s- 1

Q. Calculate the rate of emission of quanta per second, when a $25 w a tt$ bulb emits monochromatic yellow light of wavelength $0.57 μ m$ .

$7.17 \times 1 0^{29} s^{- 1}$

$7.17 \times 1 0^{11} s^{- 1}$

$7.17 \times 1 0^{9} s^{- 1}$

$7.17 \times 1 0^{19} s^{- 1}$

Q. Calculate the rate of emission of quanta per second, when a 25watt bulb emits monochromatic yellow light of wavelength 0.57μm .

7.17×1029s−1

7.17×1011s−1

7.17×109s−1

7.17×1019s−1

photonE​=λhc​=0.57×10−66.625×10−34×3.0×108​=34.86×10−20J . Watt=No.ofphotonssec.emitted​×photonE​(Watt=25Js−1) . 25=No.ofphotons×34.86×10−20 ∴ No. of photons emitted =34.86×10−2025​=7.17×1019s−1

Q. Calculate the rate of emission of quanta per second, when a $25 w a tt$ bulb emits monochromatic yellow light of wavelength $0.57 μ m$ .

$7.17 \times 1 0^{29} s^{- 1}$

$7.17 \times 1 0^{11} s^{- 1}$

$7.17 \times 1 0^{9} s^{- 1}$

$7.17 \times 1 0^{19} s^{- 1}$