m2 m Laboratory system m2 7.18. A particle of mass m with an initial kinetic energy T makes an elastic collision with a particle of mass m2 initially at rest. m is deflected from its original direction with a kinetic T through an angle o' as in figure above. Letting a = m2/m and y = coso, show that the fractional kinetic energy lost by m, AT/T = (T - T')/T, is given by 2y AT 2 T 1+a 1+0 (7a+32-1)