Wavelength is defined as distance between two troughs or two crests !!
so in this wavelength is 4 metres !!
A.gold is the answer. As it's density is 19.32 grams per cubic centimeter which is lot more than the other substances.
Talk about the jobs that pipeline construction provides to citizens and wether or not it’s effects are ultimately eco-friendly
If it produces 20J of light energy in a second, then that 20J is the 10% of the supply that becomes useful output.
20 J/s = 10% of Supply
20 J/s = (0.1) x (Supply)
Divide each side by 0.1:
Supply = (20 J/s) / (0.1)
<em>Supply = 200 J/s </em>(200 watts)
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Here's something to think about: What could you do to make the lamp more efficient ? Answer: Use it for a heater !
If you use it for a heater, then the HEAT is the 'useful' part, and the light is the part that you really don't care about. Suddenly ... bada-boom ... the lamp is 90% efficient !
