Only a fraction of the electric energy supplied to a tungsten lightbulb is converted to visible light. The rest of the energy shows up as infrared radiation (i. e., heat). A 25−W lightbulb converts 15.0 percent of the energy supplied to it into visible light (assume the wavelength to be 505 nm). How many photons are emitted by the light bulb per second (1 W = 1 J / s)

The value is  

Explanation:

From the question we are told that

  The power rating of the bulb is  P  =  25 W    

   The efficiency is

     The wavelength is

Generally the energy of the photon emitted is mathematically represented as

Here  h is the planks constant  with a value  

         c is the speed of light with value  

So

=>      

=>      

Generally we are told that 1 W =  1 J/s  

  Hence  25 W  =  25 J  

Generally the amount of this energy converted to light is  

Generally the number of photons that are emitted by the light bulb per second  is mathematically represented as

=>  

so here is the information for current research:

-nrel's geothermal analysts, scientists, and engineers perform a full range of research from developing advanced methods of locating and accessing geothermal resources to exploring innovative technologies to extract and produce clean energy from the heat of the earth

and here is the information for the technology of geothermal energy:

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-resources of geothermal energy range from the shallow ground to hot water and hot rock found a few miles beneath the earth's surface, and down even deeper to the extremely high temperatures of molten rock called magma

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-a geothermal heat pump system consists of a heat pump, an air delivery system (ductwork), and a heat exchanger-a system of pipes buried in the shallow ground near the building

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