1. do you feel the ends of the ruler pushing against your hands? 2. what will happen to the ruler as you release it?

3. what was stored as you bent the ruler using your left hand?

4. what will happen to the ruler as you take away your left hand quickly?

Due to stored energy, the ruler moves in forward direction.

Explanation:

When we bent the ruler from its original position, energy is stored in the ruler so when we remove the hands from the ruler so it moves in the forward direction. When the ruler reaches to its original position so due to more stored energy, it moves more forward than its original position and vibrate on its mean position and finally remain at rest after sometime.

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explanation: