Final answer:
The discharge of a conical pile in static discharges can be caused by high humidity, dry conditions, and sharp objects, which can all affect the behavior of static electricity.
Step-by-step explanation:
What causes the discharge of a conical pile in static discharges? The potential causes include high humidity, dry conditions, and the presence of sharp objects. All of these factors can influence the buildup and release of static electricity. Rubbing materials together can generate static electricity due to the transfer of electrons, such as rubbing a balloon on your hair causing it to stick to a wall. Dry conditions, like those found in a dryer, can intensify static cling, making closer contact possible. Sharp objects can concentrate electric fields, leading to a discharge.
Most objects do not exhibit static electric effects because in a neutral object, the amounts of positive and negative charges are balanced, and thus cancel each other's effects out. However, when objects are rubbed together or come in contact with another material that can transfer charge, static electricity can become apparent.