Sometimes, we can determine whether a structure is stable or not from our intuition, even we do not learn any physics ideas. We got that kind of intuition from our daily experience. However, the daily experience can be very tricky. Look at the picture below, do you believe they are really existed or some magics.
The answer is they are true. SURPRISE! OK, let me to explain the principal with the second picture. We consider the hammer and stick is a whole system. The system is stable because it has two equivalent forces: the supporting force of the desk and the gravity of the earth. As long as the two forces are in a line, the system has a chance to be stable. In the second picture, the most mass concerns in the head of hammer. The supporting force exists on the left side of the stick. If we design the configuration, the two forces are in a line. Second, we should consider the rotation of the system. Similarly, we can design the configuration in order to let the stick has a zero torque.
So believe your eyes, even though it may unbelievable.
the phenomena in the two pictures are so amazing. I think it is the great physics. do you do it by yourself?
ReplyDeleteI did not do the experiments. But my friends did. It is kind of unbelievable.
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