Question

A billiard ball of mass m = 0.25 kg strikes the cushion of a billiard table at ?₁ = 50

Answer 1

Final momentum of the ball is

            P_fx = - mV_f cos 55^o

                  = -(0.25 kg)(10 m/s) cos 55^o

                  = - 1.433 kgm/s

           P_fy = m V_f sin 55^o

                 = (0.25 kg)(10 m/s) sin 55^o

                 = 2.047 kgm/s

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Initial momentum of the ball is

       Pix = m Vi cos 52

             = (0.25 kg)(22 m/s) cos 49^o

              = 3.608 kgm/s

       Piy = m Vi sin 49^o

            = (0.25 kg)(22 m/s) sin 49^o

             = 4.150 kg m/s

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Change in momentum is

        Px = ( - 1.433 kgm/s ) - (3.608 kgm/s ) = -5.041 kg m/s

        Py = (2.047 kgm/s) - (4.150 kg m/s) = -2.103 kg m/s

   magnitude is ? [Px^2 + Py^2 ] = ?[ 5.041 kg m/s)^2 + (2.103)^2 ]

                         = 5.462 kg m/s