Geiger nuttal law.
Geiger & nuttal measured the range of alpha particles emitted by several radioactive elements & found that there exists a regular relationship between the ranges & the half lives of the elements. The relationship is expressed as log10(λ)=A+Blog10(R) Where, R=Range of alpha particles λ=disintegration constant A & B = constant ★ Geiger nuttal law in terms of energy log10(λ)=K+Clog10(E) Where,E=energy of alpha particles K & C = constant ★ shorter half lives alpha particles have greater kinetic energy.while longer half lives alpha particles have lower kinetic energy.