Final answer:
To make threading electrode wire easier, one should use a lubricant. This assists in the threading process by reducing friction without changing the wire's size or flexibility.
Step-by-step explanation:
To make threading electrode wire easier, the correct answer is C) Use a lubricant. Increasing the wire diameter could make it more difficult to thread through a small opening, while decreasing the wire diameter might make the wire too weak or flexible for threading. Using a lubricant, however, can reduce friction and make the threading process smoother without altering the physical characteristics of the wire.
If we look at similar principles in electricity, reducing resistance during transmission is desirable as it helps to reduce energy loss. For example, in the context of electrical circuits, if you want to increase the power dissipated, you should reduce the resistance to increase the power, given that the current remains constant, according to the relationship P = I2R (power equals current squared times resistance).
Focusing on the subject of wire resistance, when a wire is stretched to four times its original length, its resistance increases by the square of the factor by which it is stretched. Therefore, if a wire's length is made four times longer, its resistance increases by a factor of sixteen, because resistance is directly proportional to the length of the wire and inversely proportional to its cross-sectional area.