However, a simple two-dimensional density plot of this function immediately gives us a good feeling for the simple and beautiful symmetry contained in the original formula.
For example, to model the sound of a drum, there would be a formula for how striking the drumhead injects energy into a two dimensional membrane.
举例来说，对于模拟鼓声，将有一个公式阐明敲击鼓面加添能量到二维的膜。
3
Here, an approximate formula educed by dimensional analysis is presented, which involves fracture velocity and loading rate, to calculate kinetic energy increment.