To determine the net force in this scenario, we can assign values to the forces. The downward force exerted by the man is -100 N, and the upward force exerted by the spring is +150 N.
The net force (F_net) can be calculated as follows:
F_net = (upward force) + (downward force)
F_net = 150 N + (-100 N)
F_net = 150 N - 100 N
F_net = 50 N
Therefore, the net force of this system is 50 N.