You continue to push on a door when, according to a sign on that door, you should try pulling open the door instead. Which barrier to problem solving are you failing to overcome?

mental set

Explanation: Problem solving could simply be defined as a set of processes required to proffer solution or find answers to a problem. The most commonly identified barriers to problem solving include ; confirmation bias, mental set, functional fixedness, unnecessary constraints, and irrelevant information.

In the scenario above, the barrier to problem solving the individual is failing to overcome is the mental set, which could be explained when an individual is rigid on a particular method or procedure adopted in solving previous problems. There is every possibility that, the individual was successfully able to open previous doors by pushing the door and has become inclined to the idea of pushing on all doors to gain entry.

question - in 1827, john walker, a druggist in a small english town, tipped a splint with sulphur, chlorate of potash, and sulphid of antimony, and rubbed it on sandpaper, and it burst into flame. the druggist had discovered the first friction-chemical match, the kind we use to-day. it is called friction-chemical because it is made by mixing certain chemicals together and rubbing them. although walker's match did not require the bottle of acid, nevertheless it was not a good one. it could be lighted only by hard rubbing, and it sputtered and threw fire in all directions. in a few years, however, phosphorus was substituted on the tip for antimony, and the change worked wonders. the match could now be lighted with very little rubbing, and it was no longer necessary to have sandpaper upon which to rub it. it would ignite when rubbed on any dry surface, and there was no longer any sputtering. this was the phosphorus match, the match with which we are so familiar. according the paragraph what was the benefit of the new phosphorus match? it burst into flame when rubbed on sandpaper. it was made by mixing chemicals. it could be ignited on any dry surface. it threw fire in all directions.

answer - matches required natural chemicals