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strength=Abbas

Anyone good at physics plz help

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So this is the qiestion :

Estimate the number of photons emitted by a 65W incandescent light bulb in one minute. (Assume all the emitted photons are yellow. Not that an average incandescent light bulb can only convert 2.2% of the electricity it uses into visible photons.)

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47 minutes ago, ali_fatheroforphans said:

@Ruqaya101 she's on fire atm, I'd expect her to answer this question of yours.

uhm uhm. I got this. This a piece of cake!

But brother, please, why you do the to me? I thought I got rid of physics, it still haunts me, and now you tag me in this... this... outrageous nightmare. 

anyways, Allah guide you brother and forgive you for your shortcomings

49 minutes ago, ali_fatheroforphans said:

I'd expect her

damn, when I read that though, I was like hallah hallah, im still a role model!

1 hour ago, strength=Abbas said:

Estimate the number of photons emitted by a 65W incandescent light bulb in one minute. (Assume all the emitted photons are yellow. Not that an average incandescent light bulb can only convert 2.2% of the electricity it uses into visible photons.)

Sellam brother, okay listen yeah, after too many mistakes and finally a right answer ill explain it to you in the simplest form possible.

its asking you to find an estimate of the photons emitted by a light bulb with a voltage of 65W in one minute, ONE minute. now the side note is that its telling us the light bulb converts a percentage of 2.2 electric wise. 

therefore, just multiply the voltage by the percentage to get the

2.2/100 * 65 to get 1.43 w

now you need to find the energy of a single photon which is just hc/lambda of the visible colour which is yellow

didn't know what the lambda was so had to do a little research... 

1 hour ago, ali_fatheroforphans said:

ali_fatheroforphans

I still cant believe youre making me do this!

 my research says that the lambda for yellow light is 550!

Wavelengths of the visible region of the spectrum range from 700 nm for red light to 400 nm for violet light.

    red 700 nm
 orange 630
 yellow 550
  green 500
   blue 450
 violet 400

Photons - bundles of electromagnetic energy

In his research on the radiation from a hot (black) body, Max. Planck made a simple proposal. He suggested that light consists of photons. The energy, E, of each individual photon of a monochromatic light wave, is proportional to the frequency, n, of the light:

where h (= 6.626*10-34 J s) 

29,979,245,800 cm/sec (3 x 1010 approx) = C which is speed of light.

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12 minutes ago, Ruqaya101 said:

its asking you to find an estimate of the photons emitted by a light bulb with a voltage of 65W in one minute, ONE minute. now the side note is that its telling us the light bulb converts a percentage of 2.2 electric wise. 

therefore, just multiply the voltage by the percentage to get the

2.2/100 * 65 to get 1.43 w

now you need to find the energy of a single photon which is just hc/lambda of the visible colour which is yellow

didn't know what the lambda was so had to do a little research... 

Imagine writing all that in an exam for a simple 2 mark question.

13 minutes ago, Ruqaya101 said:

I thought I got rid of physics, it still haunts me, and now you tag me in this... this... outrageous nightmare. 

This was perfectly planned, wanted you to end you day with some physics.

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1 minute ago, ali_fatheroforphans said:

This was perfectly planned, wanted you to end you day with some physics.

yeah bro, shows you are genuine and thoughtful aye? I puked on my exam today:hahaha:, and now you make me do physics

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3 minutes ago, Ruqaya101 said:

yeah bro, shows you are genuine and thoughtful aye? I puked on my exam today:hahaha:, and now you make me do physics

Yup, lol to put the icing on the cake.

Edited by ali_fatheroforphans

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Salam Aleykoom,

As an (ex-)physics graduate myself, i concur with:

On 11/21/2018 at 4:32 PM, Ruqaya101 said:

I thought I got rid of physics, it still haunts me, and now you tag me in this... this... outrageous nightmare

Easily the worst period of my life hahaha.. ha... ... I never think about those days without thanking Allah (azwj) they are finally over.

I also concur with @Ruqaya101 and @hasanhh respectively in terms of train of thought and result.

Wa Salam

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