In the system shown in the fig. there is no friction and string is light. Mass of movable pulley

In the system shown in the fig. there is no friction and string is light. Mass of movable pulley

In the system shown in the fig. there is no friction and string is light. Mass of movable pulley `P_(2) \"is\" M_(2)`. If pulley `P_(1)` is massless, what should be value of applied force F to keep the system in equilibrium?