Explain how planetesimals differ from protoplanets.
Making Comparisons Write a description of the evaporative method of desalination using terms from the water cycle.
In 1911, Ernest Rutherford modeled an atom as being a point of positive charge Ze surrounded by a negative charge -Ze uniformly distributed in a sphere of radius R centered at the point. At distance r within the sphere, the electric potential is
V=Ze4πε0(1r−32R+r22R3).V = \frac { Z e } { 4 \pi \varepsilon _ { 0 } } \left( \frac { 1 } { r } - \frac { 3 } { 2 R } + \frac { r ^ { 2 } } { 2 R ^ { 3 } } \right). V=4πε0Ze(r1−2R3+2R3r2).
(a) From this formula, determine the magnitude of electric field for
0≤r≤R0 \leq r \leq R 0≤r≤R
. What are the (b) electric field and (c) potential for
r≥Rr \geq R r≥R
?
What is the difference between supervised and unsupervised machine learning?
