It relates the rates of change of a quantity to the instantaneous value of that quantity. Both KVL and KCL will yield differential equations whenever a network contains C's or L's. 1ns which is fed to a simple RC circuit. A very fast fall time is used so that one can measure the RC time constant with some accuracy. We'll use the waveform cursor that appears whenever the mouse is positioned in the plot window so that is underneath some portion of a waveform.
Jade positions the cursor on the first waveform found above the current mouse position.
As one moves the mouse, the waveform cursor tracks the waveform and the readout on the upper left hand corner of the window changes to reflect the current time and waveform voltage. 1ns which is fed to a simple LC circuit. A very fast rise time is used so that one can measure the period of the oscillation with some accuracy. Then using the scrollbar move the waveform until the 5th and 7th crossing of the 1v level are visible in the plot window. Now, click and hold down the mouse button while dragging the second cursor to the right until you've reached the 7th crossing of the 1v level, i.e., one whole period of the oscillation.