Optics Question 178
Question: A laser beam can be focussed on an area equal to the square of its wavelength A He-Ne laser radiates energy at the rate of 1mW and its wavelength is 632.8 nm. The intensity of focussed beam will be
Options:
A)
B)
C)
D) None of these
Show Answer
Answer:
Correct Answer: B
Solution:
Area through which the energy of beam passes
