The radius of the disk is R, and the mass of the disk is M. Using the parallel axis theorem and theequation for the moment of inertia of a disk about its central axis developed in the previous example, Eq. (8), the moment of inertia of the disk about the specified axis is Fig.
Short Circuits. Short circuits are the second most common reason for breaker tripping and are a more serious concern. Short circuits occur when the black hot wires inside your electrical service panel come in contact with either other hot wires or neutral wires.
If a homeowner is hammering a nail through a wall, and the nail comes into contact with two wires, it can establish a connection. The same thing happens when the coating is stripped from wires that can come into contact. Short circuits can also occur in batteries. If the positive and negative terminals are connected by a wire, a surge of electrical current can generate sufficient heat to cause an explosion. To prevent short circuits in homes, electricians install fault protection devices, such as circuit breakers and fuses, that shut down the electrical current when the system detects a surge.