Why is it so easy for you to use a screw driver to loosen/tighten screws, but nearly impossible/very hard to do it with just your hand?
In: Physics
Levers convert a small force applied over a long distance to a large force applied over a small distance. A long lever lets you lift a heavy weight with less apparent effort.
The rotational equivalent of linear force is torque. The handle on a screwdriver has a larger diameter than the screw head. The wider the handle, the less apparent effort has to be used.
It’s also easier to grip the screwdriver. You use different, stronger muscles to make a fist (around the handle) than you do to pinch (the screw) with your fingertips.
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