Question

A narrow beam of `X-`ray radiation of wavelength `62pm` penetrates an aluminium screen `2.6 cm` thick. How thick must a lead screen be to attenuate the beam just as much? The mass absorption coefficients of aluminium and lead for this radiations are equal to `3.48` and `72.0 cm^(2)//g` respectively.

Answer 1

We require `mu_(Pb)d_(Pb) = mu_(Al)d_(Al)`
or `((mu_(Pb))/(rho_(Pb)))rho_(Pb)d_(Pb) = ((mu_(Al))/(rho_(Al))) rho_(Al)d_(Al)`
`72.0 xx 11.3 xx d_(Pb) = 3.48 xx 2.7 xx 2.6`
`d_(Pb) = 0.3mm`