What overall weight does a painter's scaffold need to support if it is carrying two painters with weights of 500N and 400N and has a reading of 800N on one scale?

To determine the overall weight that the painter's scaffold needs to support, you begin by adding the weights of the two painters together. In this scenario, one painter weighs 500N and the other weighs 400N. When you sum these weights, you find:

500N + 400N = 900N

This total of 900N represents the combined weight of the two painters.

Next, one scale on the scaffold reads 800N. This means that this scale is supporting a portion of the total weight of the two painters. To find out how much weight the scaffold supports in total, you can consider that the remaining weight must be supported by the other scale or the structure itself.

The total required support would then be calculated as:

Total weight supported = Weight of the first painter + Weight of the second painter = 900N

Since one scale reads 800N, the remaining weight that needs to be supported actually corresponds to what the other scale must be sharing, which is:

900N total weight - 800N from one scale = 100N left to be supported.

Therefore, the overall weight that the scaffold must support is the total weight of the two painters, which is 900N. The scales have divided the