The screwdriver uses the working principle of lever when it is used to pry the paint cover. The larger the distance between the power point and the pivot point, the more labor-saving it is, so it is more labor-saving to be screwdriver longer than screwdriver shorter.
When a screwdriver is used to twist screws, the working principle of the axle is used. When the wheel is bigger, it is more labor-saving, so it is more labor-saving to use screwdriver of the thick handle than screwdriver of the thin handle to screw.