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TJDF
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Homework Statement
A pulsed dye laser emits light of wavelength 576 nm in pulses of 456 µs duration. This light is absorbed by the hemoglobin in the blood and can therefore be used to remove vascular lesions, such as certain blemishes and birthmarks. To get an estimate for the power required for this laser surgery, assume that blood has the same specific heat capacity (4190 J/(kg·K)) and heat of vaporisation (2.256×106 J/kg) as water. Suppose that each pulse must remove 2.5 µg of blood by evaporating it, starting at 33 °C.
a) How much energy must the pulse deliver to the blemish?
b) What must be the power output of the laser?
c) How many photons does each pulse deliver?
Homework Equations
Q = m*c*delta(t)
f = c/wavelength
E = h*f
The Attempt at a Solution
I don't even know how to start this... but I'd really appreciate the help, especially an answer to part a.