Hector read that the traditional drink in Tibet is tea withadded butter. Inspired by this idea, he decides to investigate howa thin layer of fat on the top of a hot liquid affects the coolingof the liquid. He performs two different experiments.
Experiment 1: Hector pours 100 ml of boiling water intoeach of two Styrofoam cups and adds a thin (2.0-mm) layer of hotoil (at about 100∘C ) to one of the cups. He measures the initialtemperature in the cups, waits for 10 minutes, and then measuresthe temperature again. His measurements are shown below.
| Cup A
(no oil) | Cup B
(with layer of oil) |
| Ti | 98∘C | 98∘C |
| Tf | 84∘C | 95∘C |
Experiment 2: Hector puts two empty Styrofoam cups onseparate precision scales and zeroes the scales. Then he pours 100ml of boiling water into each cup and adds a 2.0-mm layer of hotoil to one of the cups. He records the initial readings of thescales, waits for 10 minutes, and then records the readings of thescales again. His data are shown below.
| Cup A
(no oil) | Cup B
(with layer of oil) |
| mi | 99.00 g | 104.00 g |
| mf | 97.00 g | 104.00 g |
The surface area of the water in the cups is 3.0×10−3m2.
Part F
What other quantities relevant to the investigation can bedetermined or estimated from Hector's data?
a) The density of water
b) The number of moles of water
c) The rate of evaporation of oil
d) The density of oil
