Haynes-shockley experiment is used to calculate the hole life time (tau)τp in an n-type sample. assume that the peak voltage of the pulse displayed on the oscilloscope screen is proportional to the hole concentration under the collector terminal at time td and that the displayed pulse can be approximated as a gaussian distribution which decays due to recombination by exp(-t/τp ) . the electric field is varied and the following data are taken: for td = 200 μs, the peak is 20 mv; for td = 50 μs, the peak is 80 mv. determine tp based upon the above measurement results.