- Why is it easier to balance something on your palm than on your
fingertip?
A fingertip is a smaller base than the palm of your hand, and balancing requires at least one of the same conditions as STANDing - that the center of gravity be directly above the base. It is harder to make sure the middle of an object is directly above the small tip of a finger than it is to make sure it is above the much larger, flatter area of the hand.
- This model crane has supports that extend from the sides, which
can be found on real cranes. What are these for?
The supports extend the base of the crane, allowing the arm of the crane, which might be carrying a load almost as heavy as the crane itself, to extend further out without the center of mass going past the base!
- The small 'house' on the end of this 1892 crane protected some
of the heavy machinery that made the crane run. Why is it extended out
over the base?
The extra machinery serves a second use as a counterbalance. By extending the weight of the machinery to the left, more weight can be carried on the right without moving the center of gravity past the base.
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