Chapter 2, Problem 2.36P

To determine

To Find:

The derivative:

  $\frac{dE}{dt}=\frac{\partial E}{\partial p_x}\frac{d{p}_x}{dt}+\frac{\partial E}{\partial p_y}\frac{d{p}_y}{dt}+\frac{\partial E}{\partial p_z}\frac{d{p}_z}{dt}$