I have a light bulb and i'm trying to figure out what the intensity of it is. This is because I have a solar cell and i'm trying to measure the efficiency of it. I know the power out from the solar cell and now all i need to know the power into the solar cell. I have a lightbulb that's spherical. It says that its 320 lumens, uses 40 watts. It's also a soft incendescent lightbulb. From this infomration am I able to determine the amount of energy the light emitted has?