Homework Statement
Compare the deBroglie wavelength for an electron in the n=6 orbit of He+ compared to the n=2 orbit. Is the deBroglie wavelength the same, smaller, or larger? Derive this.
Homework Equations
Quantization of Paths of Electrons:
2 pi r = n (lambda)
Bohr Radius:
rn=n2 aB
The...
Ok I think I am getting close to this one:
c=\sqrt{\frac{2GM}{R}}
M=\frac{c^2 R}{2G}
Using the Heisenberg Principal:
\DeltaX \DeltaP = \frac{h_bar}{2}
\DeltaP = c M
Solving this for \DeltaX
\DeltaX = \frac{G h_bar}{c^3 R}
How do I get the square root and get rid of the R...
Homework Statement
a. The first part of this problem was to derive the escape speed (Vesc) for a star of mass M and radius R.
b. The second part is where I am having trouble. It says to equate the Vesc calculated above and derive a formula for Planck length in terms of c, G, and h_bar...
Ok thanks for the help, just wanted to make sure I wasn't making a stupid mistake. Its so nice that my $120 textbook can't answer its own problems correctly. :mad:
I got the Y centroid coordinate to work out to the books answer, so that one is all good. Its just that the X centroid coordinate that I have calculated is 90.33 mm, while the book says it should be 87.3 mm. So is the book wrong? (I don't think rounding error could account for a 6 mm...
My calculations are for the X coordinate of the centroid with reference being the left edge of the shape. I divided it up into an 80x80 square for the left part, an 80x120 rectangle for the right with a semi-circle of with radius 40mm ontop of it. The cutout is a circle with radius 20mm. Its...
Homework Statement
Determine The Centroid of The Area
Homework Equations
x_centroid = [(Area of each piece)(Centroid of each piece)]/(Area of each piece)
The Attempt at a Solution
This seems like a really basic problem, I am just reviewing for my statics final on saturday. The only problem...