Answer:
The weight of the board is 200 N
Step-by-step explanation:
Translational Equilibrium
An object is in translational equilibrium if the velocity of its translational motion is constant or if it's at rest.
The painter is standing on the single board scaffold, obviously at rest. This means the sum of all translational forces must be zero.
If the tensions of both ropes are T1 and T2, the weight of the painter is Wp, and the weight of the board is Wb, then:
T1 + T2 - Wp - Wb = 0
Both tensions go vertically up and both weights go vertically down.
Solving for Wb:
Wb = T1 + T2 - Wp
Wb = 550 N + 450 N - 800 N
Wb = 200 N
The weight of the board is 200 N