The number of photons per sec given off by a sixty-wattincandescent light bulb i

Question

The number of photons per sec given off by a sixty-wattincandescent light bulb is 3.6*10^18 photons/sec. The photons areemitted uniformly in all directions. From a distance of 3.1 m youglance at this bulb for 0.10 sec. The light from the bulb travelsdirectly into your eye and does not reflect from anything. Thepupil of the eye has a diameter of 2.0 mm. How many photons enteryour eye? (This problem refers to a previous one where thewavelength=wavelength of green light = 555nm)
What I have so far is D=2.0mm apperature diameter of eye H= distance to the light bulb t=0.10 seconds time spent glancing at light bulb N=3.6*10^18 photons/ sec=number of photons per sec
So the total number of photons emitted np=3.6*10^18photons/sec*0.10 sec=3.6*10^17 sec.
I don't know how to continue from here, that is if I am on theright track. The answer in the back of the book is 9.4*10^9 photons
I appreciate any help and I will rate very well. (This problem refers to a previous one where thewavelength=wavelength of green light = 555nm)
What I have so far is D=2.0mm apperature diameter of eye H= distance to the light bulb t=0.10 seconds time spent glancing at light bulb N=3.6*10^18 photons/ sec=number of photons per sec
So the total number of photons emitted np=3.6*10^18photons/sec*0.10 sec=3.6*10^17 sec.
I don't know how to continue from here, that is if I am on theright track. The answer in the back of the book is 9.4*10^9 photons
I appreciate any help and I will rate very well.

Explanation / Answer

   No. of photons emitted per unit solid angleper second    N   =   totalno. of photons emitted per second /4   =   3.6 * 1018 / 4* 3.14   =   2.86 *1017   photons / sr-s    Solid angle formed by pupil ofeye      =   areaof pupil / distance2       =   * (2.0 * 10-3 / 2)2 /3.12   =   3.27 *10-7  sr    No. of photon incident into theeye   =   solid angle of pupil * N *time    neye   =   3.27* 10-7 * 2.86 * 1017 *0.1   =   9.35 *109   ˜   9.4* 109   photons       =   * (2.0 * 10-3 / 2)2 /3.12   =   3.27 *10-7  sr    No. of photon incident into theeye   =   solid angle of pupil * N *time    neye   =   3.27* 10-7 * 2.86 * 1017 *0.1   =   9.35 *109   ˜   9.4* 109   photons

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