Final answer:
To find the initial acceleration of the block, apply Newton's second law using the formula a = F/m, where F is the net force and m is the mass of the block. Considerations should include tension, gravity, and any applied forces in the block system.
Step-by-step explanation:
The question pertains to Newton's second law of motion which states that the acceleration of an object as produced by a net force is directly proportional to the magnitude of the net force, in the same direction as the net force, and inversely proportional to the mass of the object. To determine the initial acceleration of the block, one can use the formula derived from Newton's second law, a = F/m where F is the net force acting on the block, and m is the mass of the block.
In the specific scenario described, we do not have the net force explicitly mentioned, but there are details about tension in the rope and the possibility of an applied force or friction involved. These must be considered when determining the net force acting on the block system. The initial acceleration can be calculated using the information provided about the masses of the blocks and any applied force or the tension in the rope if enough information about the system is given.
For instance, if one block is on a table (mass 4.0 kg) and one is hanging (mass 1.0 kg) and the surface is frictionless, the acceleration of the system can be found considering the gravitational force acting on the hanging mass and the tension in the rope. This gives us an acceleration commonly represented as a = g(m2)/(m1+m2) where m1 and m2 are the masses of the blocks on the table and the hanging block respectively, and g is the acceleration due to gravity (9.8 m/s²).