Archives of Ask A Scientist!
About "Ask A Scientist!"
On September 17th, 1998 the Ithaca Journal ran its first "Ask A Scientist!" article in which Professor Neil Ashcroft , who was then the director of CCMR, answered the question "What is Jupiter made of?" Since then, we have received over 1,000 questions from students and adults from all over the world. Select questions are answered weekly and published in the Ithaca Journal and on our web site. "Ask A Scientist!" reaches more than 21,000 Central New York residents through the Ithaca Journal and countless others around the world throught the "Ask a Scientist!" web site.
Across disciplines and across the state, from Nobel Prize winning scientist David Lee to notable science education advocate Bill Nye, researchers and scientists have been called on to respond to these questions. For more than seven years, kids - and a few adults - have been submitting their queries to find out the answer to life's everyday questions.
Now suppose you took your glass of water from the countertop and sealed it inside a somewhat larger, airtight container. What do you think would happen? If you observe the process over a period of time, you will see the water level drop initially and then (if you started with enough water) evaporation will seem to stop. Your closed system has reached equilibrium: There is enough water vapor in the closed container that molecules are condensing back onto the surface at the same rate as they evaporate. The rate of evaporation is different for different liquids. For instance, alcohol evaporates more quickly than water, while oils takes much longer.
The rate of evaporation also depends on the temperature of the liquid and its surroundings. Some heavy oils (or exotic liquids like liquid mercury) may need to be heated before they show appreciable evaporation.
If you raise the temperature of a liquid enough you can start a process of evaporation within the liquid itself. This process is another very familiar one-it's called boiling!
- What are MEMS and why are they an important scientific break through?
- What forces make a volcano erupt?
- What causes the electron within an atom to emit photon packets? We were told to make a diagram of it. What causes the electron to skip down a level and emit photons?
- How come ice skates slide over ice so easily when hydrogen bonds usually make things stick?
- I am currently studying electronics and how they work together to perform work. But I seem to get confused when the term "ground" is used. I understand that it is a "zero" reference point, and that it is a common return path for electrons to earth ground. I get stumped though when I see a schematic that has a ground attached to the negative end of a battery terminal in a dc circuit. Why don't the electrons just flow straight to ground? Then in an AC circuit schematic, I see a ground connection again connected to the negative side of a circuit. Can I assume that the ground is positively polarized which attracts the electrons?
- In an empty charged sphere, even though the charge is evenly distributed on the surface, why does it behave as if it is all in the center? (The same as gravity)
- How do MRI's work? What are all the ticking and banging noises?
- How does a fluorescent light bulb work?
- What would happen if a tornado started in the southern hemisphere and progressed into the northern hemisphere? Would it change directions?
- How is it that no matter where a person stands on earth they are always upright? Why aren't people in Antarctica upside down?