In the figure a block A of mass m is attached at one end of a light spring and the other end of the spring is connected to another block B of mass2m through a light string. A is held and B has obtaiwwned equilibrium. Now A is released. The acceleration of Ajust after that instant is a. The same thing is repeated for B.In that case the acceleration of B is b, then the value of a/b is __________.