Final answer:
There is a greater start-up force required when moving an object due to static friction, which exceeds kinetic friction. Understanding static vs. kinetic friction is essential for applying Newton's laws of motion to solve physics problems.
Step-by-step explanation:
When dragging an object, there is a greater start-up force required due to static friction, which is the resistance between two surfaces that are not moving relative to each other. Once an object begins to move, the force required to keep it moving is typically less because the kinetic friction, which acts when surfaces slide over each other, is usually lower than static friction. Understanding the difference between static and kinetic friction is significant for solving problems that involve Newton's laws of motion, especially when determining if a situation requires Newton's first law (net force = 0 and velocity is constant) or Newton's second law (net force is not zero, thus causing acceleration).
Explanation for the start-up force being greater lies in how static friction can be stronger than kinetic friction, responding to applied forces by matching them until a threshold is met. Once in motion, because kinetic friction between surfaces is less, it is easier to maintain motion than to start it. These principles are also applicable in cases involving drag force, which is a resistant force exerted by a fluid (such as air or water) against the motion of an object, though drag is often more complex and dependent on velocity, shape, size, and other factors.