All Problems Laws of Conservation
Problem 1.176
Three identical \(\operatorname{discs} A, B,\) and \(C\) (Fig. 1.45 ) rest on a smooth horizontal plane. The disc \(A\) is set in motion with velocity \(\mathbf{v}\) after which it experiences an elastic collision simultaneously with the discs \(B\) and \(C .\) The distance between the centres of the latter discs prior to the collision is \(\eta\) times greater than the diameter of each disc. Find the velocity of the disc \(A\) after the collision. At what value of \(\eta\) will the disc \(A\) recoil after the collision; stop; move on?
1.176. \(\mathrm{v}^{\prime}=-\mathrm{v}\left(2-\eta^{2}\right) /\left(6-\eta^{2}\right) .\) Respectively at smaller \(\eta\) equal, or greater than \(V \overline{2}\).