As we all know, force applied to a spring is directly proportional to the extension of spring as shown below : However, the experiment results don't match with it. Why is this happening? I don't think systematic error is the reason that is causing the experimental graph to move away from t...

How can energy have inertia? To my intuition, inertia is so closely associated with mass that my intuition says "Huh?" Indirectly by mass energy equivalence it works fine, for example: I have a closed system, and add energy. Now it has more mass according to $E=mc^2$, and the inertia associa...