What does it mean when one says that "A circle and an ellipse with a focus at the circle’s
center can touch each other only at the longer axis"?
Can't you, by varying the size of the circle, make it intersect the ellipse in a variety of ways?
An object suspended in water is lifted out of the water. How does the absolute pressure at the bottom of the water change?
The Attempt at a Solution
Wouldn't the absolute pressure not change if the object is still directly over the water...
An electron is enclosed in a large rectangular box. Considering gravity, estimate the order of magnitude of the thickness of the layer that is occupied by the electron at the bottom of the box.
I thought about this for a long time and I really have no idea how to proceed. Any thoughts?