Last Problem:
If you drop a coin and a small slip of paper at the time, the coin will inevitably reach the ground at the same time. The coin lands on the ground first because of air resistance which slows the descent of the paper.
Figure out a way to demonstrate that the coin and the paper ought to fall at the same rate as the paper in the absence of air resistance, even in a normal room on the earth. The room is on the earth, not the moon!
Answer:
To eliminate the difference in air resistance, place the slip of paper on top of the coin. Then, drop the coin, giving it a slight spin to keep it horizontal as it falls. The coin and the paper should fall together.
Today’s Problem:
Which will weigh more – a cubic meter of large steel balls or a cubic meter of small steel balls? Does it make a difference that more small steel balls can be packed into the same space or container than the large steel balls?