A standard electrical plug fits into an outlet in only one way because one of the two prongs is larger than the other. This ensures that people will insert the plug properly to create a grounded circuit. This is an example of:

A33.1 g copper object is launched from a 1.5 m 30° steel incline positioned on the floor by being pulled up a string attached to a 50.0 g mass suspended vertically over a pulley. the object is projected towards a glass table where it lands when it is at the point along its trajectory with the lowest speed. it comes to a halt when it clears the opposite edge of the table. it then falls and lands on 9 physics texts each 5 cm thick that are stacked on the floor on the opposite side of the table. assume that the table does not have a ledge and the rectangular object experiences 0.05 n of air resistance as it falls towards the books. how far and how long did the object travel and how fast does it hit the books. assume that at the moment the copper object leaves the incline, the massless string and ideal pulley break off

Aplane travels 1000 miles in 5 hours .what is the planes average speed?

Which of the following is not am example of a polymer? protein nylon kevlar concreta