* Our senses are not precise enough: Our sense of touch is good for detecting pressure and temperature, but it's not sensitive enough to distinguish between a force of 1N and, say, 2N.
* 1N is a relatively small force: A force of 1N is about the weight of a small apple. It's easily overcome by the force of friction between your skin and a surface.
How to experience a force of 1N (indirectly):
* Using a scale: Hang a small object that weighs 1N (about 100 grams) on a spring scale. You'll feel the tension in the spring as it stretches to balance the weight.
* Using a string and a pulley: Attach a small object (again, about 100 grams) to a string that goes over a pulley. Pull on the string with a constant force of 1N. You'll feel the resistance from the weight of the object.
* Using a weight on your finger: Holding a small object like a coin on the tip of your finger will exert a force of roughly 1N. You might not "feel" the force precisely, but you can sense the pressure it creates on your finger.
Important note: These are all indirect ways to experience a force of 1N. You are actually feeling the effects of the force, not the force itself.
