Question

Why is it that a screw whose threads are closer together have a greater mechanical advantage than those whose threads are farther apart?

a) Increased friction
b) Reduced force needed
c) Enhanced stability
d) Faster rotation

Answer 1

A screw with closer threads has a greater mechanical advantage because it reduces the force needed to turn the screw. (option b)

Step-by-step explanation:

The reason why a screw with closer threads has a greater mechanical advantage is because it reduces the force needed to turn the screw. The mechanical advantage of a screw is calculated by dividing the circumference of the screw by the pitch (the distance between two successive threads). When the threads are closer together, the pitch decreases, resulting in a larger mechanical advantage. This means that with a screw with closer threads, you need to apply less force to achieve the same rotation.

For example, imagine you have two screws, one with a pitch of 1 mm and another with a pitch of 5 mm. If you apply a force of 10 N to both screws, the screw with a pitch of 1 mm will rotate five times more than the screw with a pitch of 5 mm. This demonstrates how the mechanical advantage is greater with closer threads, as less force is needed to achieve the same rotation.