Question

For a bulb, what is the correct wattage and luminous flux to get the luminous effeciency below 100. I mean that for example: if the wattage of a bulb is 10 and luminous 1000 lumens, then if we divide 1000 with 10 we would get the luminous effeciency 100. then the bulb would be 3 star bulb, if the effeciency is below 100, then it would be a 4 or 5 star bulb. But are are the correct wattage and lumens to get the luminous efficiency of the bulb below 100.​

Answer 1

Answer:

''A lamp giving out 1200 lm in all directions is suspended 8 m above the working plane. Calculate the illumination at a point on

the working plane 6 m away from the foot of the lamp.'''

import math as m

I = 1200/(4*3.14) #Cd (luminous intensity of lamp)

h = 8.0 #m (height)

b = 6.0 #m (breadth)

length = m.sqrt(h**2 + b**2) #m

cosQ = h/length

E = I*cosQ/length**2 #lm/m^2

print "Illumination at point =",round(E,2),"lm/m^2 ."

Answer 2

Answer:

:''A lamp giving out 1200 lm in all directions is suspended 8 m above the working plane. Calculate the illumination at a point onthe working plane ...