# social studies

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For liver tissue irradiated by the pulsed Ho:YAG laser, determine the exposure duration which the equation for heat conduction may be ignored. Assume the absorption coefficient at the Ho:YAG laser wavelength is 30cm-1 and assume the thermal diffusivity of the tissue is the same as that of water. If the threshold temperature of ablation is 150¢J, determine the threshold fluence (J/cm^2) for ablation.

• laser ablation of tissue -

I've got news for you.
This question is about the physics of ablation and heat transfer. It is not social studies.

I do not understand the ¢J units of the laser ablation threshold temperature.

Heat conduction can be ignored if the characteristic thermal conduction distance sqrt(a*t) is less than the characteristic radiation penetration depth, 1/30 cm. a is thermal diffusivity. Use that to determine t, to answer your fist question

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