RE: The shape of Earth
August 18, 2022 at 12:26 pm
(This post was last modified: August 18, 2022 at 12:27 pm by HappySkeptic.)
There is a cool way of measuring the density of something like a gold coin.
1) Measure the exact weight of the coin. Call this A.
2) Put a beaker of water on a precise scale. Measure the weight.
3) Put the coin on very light string, and dangle it in the water. Measure the new weight.
4) The difference in weight is B.
When the coin is dangled, the weight on the scale increases by the weight of the VOLUME of WATER that the coin displaces (not the weight of the coin, since it is suspended).
The fraction A/B is the density with respect to water for the coin. Since the specific density of water is close to 1, this becomes the grams/cc density for the coin.
1) Measure the exact weight of the coin. Call this A.
2) Put a beaker of water on a precise scale. Measure the weight.
3) Put the coin on very light string, and dangle it in the water. Measure the new weight.
4) The difference in weight is B.
When the coin is dangled, the weight on the scale increases by the weight of the VOLUME of WATER that the coin displaces (not the weight of the coin, since it is suspended).
The fraction A/B is the density with respect to water for the coin. Since the specific density of water is close to 1, this becomes the grams/cc density for the coin.
