Did you solve it? Do you have the brain of an engineer?

In a cranberry sorting facility, good and bad berries are separated using a trick that relies on their differing reactions when dropped onto a tilted board. The good berries, which are hard and bounce, are caught by the board and transported to a conveyor belt, while the soft bad berries, which do not bounce, fall into a discard box. This simple method ensures that nearly all good cranberries are collected while minimizing the loss of bad ones.

In the United States, medicine bottle caps are engineered to be secure against approximately 85% of children under the age of five. This percentage is not higher due to a balance between safety and practicality. If the child-resistance rate were 100%, the mechanism would also be challenging for elderly individuals and those with weak or arthritic hands.

Allowing the cap to be too difficult to open could lead to it being left off entirely, posing a greater risk than the small number of clever or strong children who might remove it.

In 2020, engineers at the Golden Gate Bridge replaced the pedestrian handrail with a new design featuring thin vertical slats instead of the previous wide horizontal sections. This change was aimed at reducing the handrail's resistance to wind, thus enhancing safety during high winds. However, the new design inadvertently resulted in two significant issues.

Firstly, the wind resistance caused the handrail to vibrate more, leading to a higher wind level experienced by cyclists. Secondly, at certain wind conditions, the handrail produced an excessive whistling noise, which could be heard for miles. This harmonica-like sound was an unintended consequence of the new slat design.

Cabin air pressure in airplanes is maintained at a level comfortable for human occupants. When an aircraft flies, the air pressure outside the plane drops significantly, creating a pressure differential that pushes outward on the aircraft's frame. In the early 1950s, the de Havilland Comet, the world's first commercial jet, experienced major crashes due to the fuselage being torn apart in mid-flight.

To prevent similar disasters, engineers at Farnborough tested the Comet's structural integrity without the plane ever leaving the ground. They achieved this by submerging the plane in a large water tank, filling the cabin with water, and increasing the pressure to simulate flight conditions. This allowed engineers to safely determine the maximum pressure the fuselage could withstand before failing.

By testing the plane in water, they avoided the destructive explosion that would have occurred if they had tested it under real flight conditions.