Given that,  Â
Puck slide total Deltax = 12mÂ
 Puck and board Mk = 0.10  Â
 Find the initial speed = ?  Â
 We know that, Â
 Vf^2-Vi^2 = 2a DeltaxÂ
 -Vi^2 = -2MkgDeltax ............(1)   Â
 then,Â
 fk = -Mk mg = maÂ
 a = -Mkg .........(2)  Â
 From equation (1),Â
 Vi^2 = 2MkgDeltaxÂ
 Vi = âš2MkgDeltax [g=9.8m/s^2]Â
 Vi = âš2(0.10)(0.98)(12)Â
 Vi = âš0.2(9.8)(12)
  Vi = âš1.92(12)Â
 Vi = âš23.52Â
 Vi = 4.8 m/s  Â
 Therefore the initial speed of the puck Vi = 4.8 m/s