0-kg mass (mA) and a 5.5-kg mass (mB) are connected to a lightweight cord that passes over a frictionless pulley. The pulley only changes the...

A 2.0-kg mass (mA) and a 5.5-kg mass (mB) are connected to a lightweight cord that passes over a frictionless pulley. The pulley only changes the direction of the force exerted by the rope. The hanging masses are free to move. Choose coordinate systems for the two masses with the positive direction up for mA and down for mB. What is the acceleration of the smaller mass.