FIX THIS: Infrared lamps are used in restaurants and cafeterias to keep food warm. The infrared radiation is strongly absorbed by water, raising its temperature and that of the food… if the wavelength of infrared radiation is assumed to be 1500mm, then the number of protons per second of infrared radiation is produced by an infrared lamp that consumes energy of the rate of 100 watt and is 12% efficient will be:
Elimination Tool
Hints
B is the right choice.
Examine E = hc/lamda.
Where,
E is the energy per photon.
h= Planks constant= 6.626-34 J/sec.
c = 3 x 108 m/s is the speed of light.
E = hc/lamda E = hc/ 1500mm
0.12 x 100= n x 6.6 x 10-34 x 3 x 108/1500 x 1019
n= 9 x 1019.
I only have one answer because it’s a numerical question.
B is the right choice.
Examine E = hc/lamda.
Where,
E is the energy per photon.
h= Planks constant= 6.626-34 J/sec.
c = 3 x 108 m/s is the speed of light.
E = hc/lamda E = hc/ 1500mm
0.12 x 100= n x 6.6 x 10-34 x 3 x 108/1500 x 1019
n= 9 x 1019.
I only have one answer because it’s a numerical question.