Final answer:
Friction impacts the overall acceleration by reducing the net force. The tension in the string depends on the magnitude of the forces. Some systems did not move due to insufficient force to overcome static friction.
Step-by-step explanation:
The presence of two different forces of friction does impact the overall acceleration of the system. Friction acts as a resistive force that opposes motion, so it reduces the net force on the system, which in turn reduces the acceleration. The greater the magnitude of the frictional forces, the greater the reduction in acceleration.
The tension inside the string at any point in the experiment depends on the magnitude of the forces acting on the system. If the frictional forces are large, they will decrease the tension in the string because less force is available to support the hanging mass.
If some systems did not move when set up, it means that the applied force was insufficient to overcome the static friction present in the system. In order to calculate the minimum force needed to overcome static friction and make the system move, you would need specific values for the coefficient of static friction and the weight of the hanging mass.