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Exercise 4 The attenuated intensity I of a neutron beam normally incident on a certain shielding material is proportional to the intensity of the beam as it passes (the distance x) through- the shield, i.e.1 dl dx Where m is the constant of proportionality. 1 If a-25 cm thick shield of this material attenuates the beam by a factor of-1,000, what thickness of the material is required to attenuate the beam by a factor of 5,000?-- Assume the incident beam has an intensity of l. when it enters the shield. I + di/1=-mx 25cm_ 1/10=10001 -+ 1000-(m*25) m=-0.276 Xem. 5000 el-z) In(5000)=-0.276*-1*x1 x=31cm