Question

When I bump one end of a long metal bar, the other end instantaneously moves. Can I use this to send messages faster than light?​

Answer 1

When you bump one end of a long metal bar, the other end does not instantaneously move. The movement would be instantaneous if the bar were perfectly rigid, but perfectly rigid materials are fundamentally impossible in the real world. Although the movement of the bar may seem uniform and instantaneous to our human eyes, it is really not. Our human eyes are simply too slow to notice the quick, but non-instantaneous, sequence of events that happens.

Answer 2

Answer:

When you bump one end of a long metal bar, the other end does not instantaneously move. The movement would be instantaneous if the bar were perfectly rigid, but perfectly rigid materials are fundamentally impossible in the real world.

Explanation:

Hope it was helpful